LETTERS
Whole-genome resequencing reveals loci under selection during chicken domestication
Carl-Johan Rubin 1*,Michael C.Zody 1,2*,Jonas Eriksson 1,Jennifer R.S.Meadows 1,Ellen Sherwood 3,
Matthew T.Webster 1,Lin Jiang 1,Max Ingman 4,Ted Sharpe 2,Sojeong Ka 5,Finn Hallbo
¨o ¨k 5,Francois Besnier 6,O
¨rjan Carlborg 6,Bertrand Bed’hom 7,Miche `le Tixier-Boichard 7,Per Jensen 8,Paul Siegel 9,Kerstin Lindblad-Toh 1,2&Leif Andersson 1,6
Domestic animals are excellent models for genetic studies of phenotypic evolution 1–3.They have evolved genetic adaptations to a new environment,the farm,and have been subjected to strong human-driven selection leading to remarkable phenotypic changes in morphology,physiology and behaviour.Identifying the genetic changes underlying these developments provides new insight into general mechanisms by which genetic variation shapes phenotypic diversity.Here we describe the use of massively par-allel sequencing to identify selective sweeps of favourable alleles and candidate mutations that have had a prominent role in the domestication of chickens (Gallus gallus domesticus )and their subsequent specialization into broiler (meat-producing)and layer (egg-producing)chickens.We have generated 44.5-fold coverage of the chicken genome using pools of genomic DNA representing eight different populations of domestic chickens as well as red jungle fowl (Gallus gallus ),the major wild ancestor 4.We report more than 7,000,000single nucleotide polymorphisms,almost 1,300deletions and a number of putative selective sweeps.One of the most striking selective sweeps found in all domestic chickens occurred at the locus for thyroid stimulating hormone receptor (TSHR),which has a pivotal role in metabolic regulation and photoperiod control of reproduction in vertebrates.Several of the selective sweeps detected in broilers overlapped genes asso-ciated with growth,appetite and metabolic regulation.We found little evidence that selection for loss-of-function mutations had a prominent role in chicken domestication,but we detected two dele-tions in coding sequences that we suggest are functionally import-ant.This study has direct application to animal breeding and enhances the importance of the domestic chicken as a model organ-ism for biomedical research.
For most of their history,domestic chicken populations have been bred for two purposes,egg laying and meat production 5.The effective chicken population size must have been huge in the past,before specialized commercial populations were established during the twentieth century,as a large proportion of farms kept a group of chickens interconnected with other groups by trade between regions,countries and continents.This is consistent with the extensive sequence diversity present in domestic chicken (,5single nucleotide polymorphisms (SNPs)per kilobase (kb)in pairwise comparisons)6.During the twentieth century,specialized layer and broiler breeds were established to circumvent the inherent conflict in selecting for
both growth traits (meat production)and reproductive traits (egg pro-duction)in the same bird.This approach,combined with the imple-mentation of modern breeding methods based on quantitative genetics theory,has been extremely successful in improving productivity 7.Our experimental design involved the resequencing of birds repre-senting eight populations of domestic chickens as well as populations of red jungle fowl (Fig.1).The aim was to identify the most common allele at the majority of polymorphic sites in the genome and to
*These authors contributed equally to this work.
1
Department of Medical Biochemistry and Microbiology,Uppsala University,Box 582,SE-75123Uppsala,Sweden.2Broad Institute of Harvard and MIT,7Cambridge Center,
Cambridge,Massachusetts 02142,USA.3Department of Cell and Molecular Biology,Karolinska Institutet,SE-17177Stockholm,Sweden.4Department of Genetics and Pathology,The Rudbeck Laboratory,Uppsala University,SE-75185Uppsala,Sweden.5Department of Neuroscience,Uppsala University,SE-75124Uppsala,Sweden.6Department of Animal Breeding and Genetics,Swedish University of Agricultural Sciences,Box 597,SE-75124Uppsala,Sweden.7INRA,AgroParisTech,UMR1313Animal Genetics and Integrative Biology,F-78350
Jouy-en-Josas,France.8IFM Biology,Linko
¨ping University,SE-58183Linko ¨ping,Sweden.9Virginia Polytechnic Institute and State University,Department of Animal and Poultry Sciences,Blacksburg,Virginia 24061-0306,
USA.Red jungle fowl
Broiler CB-1
High growth line
Broiler CB-2
Low growth line Rhode Island Red
White Leghorn WL-A
Obese strain
White Leghorn WL-B
Figure 1|Chicken lines resequenced.Schematic tree based on breeding history (branch lengths not to scale).The minimum time of divergence,when known,is indicated.Pools of genomic DNA from the following populations were resequenced:red jungle fowl (n 58),commercial broiler 1(CB-1;n 510),commercial broiler 2(CB-2;n 510),high growth line (n 511),low growth line (n 511),Rhode Island Red (RIR;n 58),obese strain (n 510),White Leghorn line 13(WL-A;n 511)and a commercial White Leghorn line (WL-B;n 58).The single red jungle fowl female from the partly inbred UCD 001line used to generate the reference genome sequence 8was also included.
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identify selective sweeps shared by populations selected for the same trait.We used the Applied Biosystems SOLiD technology to generate short reads(35base pairs(bp))to a sequence depth of four-to fivefold coverage from pools of chickens,each representing different populations,which is an effective approach for finding common alleles favoured by positive selection.The sequencing of DNA pools from individual lines is also effective for detecting selective sweeps, because heterozygosity can be calculated in sliding windows from sequences drawn from a pool of haplotypes.We sampled four dif-ferent layer populations,four broiler populations and a pool of red jungle fowl representing two different zoo populations(Supplemen-tary Table1).Finally,we resequenced the particular red jungle fowl female(from the partly inbred UCD001line)previously used to generate the classical Sanger-sequenced reference chicken genome8. The inclusion of the reference bird provided an excellent quality check of the SOLiD data.
We aligned the35-bp reads to the chicken reference sequence.The uniquely placed reads covered92%of the1,043megabases(Mb)in the current genome assembly(Supplementary Table1),and these were used for all further analyses of sequence variation.The90Mb not covered by any read from any line were mostly repetitive sequences but to some extent probably represent sequences under-represented after the emulsion-PCR step.We identified SNPs for each population individually and also for several pools of popula-tions.Three independent reads of the same non-reference nucleotide were required to declare a position polymorphic.This criterion was chosen to minimize the number of false-positives.Bioinformatic analysis showed that the great majority of SNPs(.95%)reported in this study represent true SNPs(Supplementary Information),and this conclusion was supported by experimental verification of more than300SNPs(Supplementary Table2).Furthermore,we eliminated ,40,000putative SNPs because we did not find any support for the reference allele,and assume that these represent rare sequence errors in the current assembly(Supplementary Fig.1).In total,7,453,845 SNP loci of which we are confident remained after this filtering and were used in the subsequent analyses.Supplementary Table1shows the sequence coverage and the number of non-reference alleles found in each population.We used the allele frequencies of these SNPs to construct a genetic distance tree summarizing the genetic relation-ships among populations(Supplementary Information and Sup-plementary Fig.2).
To detect putative selective sweeps,we searched the genome for regions with high degrees of fixation.The major challenge in such an analysis is to distinguish true sweeps from fixation due to genetic drift.In general,there is a high degree of genetic diversity in the chicken genome.However,some of the populations included were maintained with a limited effective population size,which could lead to genetic drift and fixation(Supplementary Table1).To lessen the problem of fixation due to genetic drift within populations,we con-ducted sweep analyses with pooled sequence data from three groups of populations selected for similar purposes:all domestic lines,the two commercial broiler lines(CB-1and CB-2)and three layer popu-lations(WL-A,WL-B and RIR).We calculated the pooled hetero-zygosity,H p,in sliding40-kb windows along the autosomes from sequence reads corresponding to the most and least frequently observed alleles at all SNP positions(Methods).
The distributions of observed H p values and the Z transformations of H p,ZH p,are plotted in Fig.2a for the three comparisons.Owing to the complex and partly unknown demography of these populations, it is difficult to define a strict threshold that distinguishes true sweeps from regions of homozygosity caused by drift.We propose that the best way to evaluate the many putative sweeps is to cross-reference these results with others such as verification of the sweep in addi-tional chicken populations and data on co-localization with major quantitative trait loci(QTLs)and differentially expressed genes.We focus our description of putative sweeps on those reaching a ZH p score of26or less,as these are in the extreme lower end of the distribution(Fig.2a).
Only,0.1%of the windows(n558)had a ZH p score of less than or equal to26in the all-domestic comparison,and the correspond-ing fractions were,0.05%for the broilers and,0.01%for the layers (Fig.2c and Supplementary Table3).We used the yellow skin allele of BCDO2locus as a proof of principle showing that this approach could reveal an established sweep4;all domestic birds in this study were assumed to be homozygous for the yellow skin allele.We observed an H p value of0.09(ZH p528.2)over BCDO2(Fig.2b), and the region perfectly overlapped the previously defined sweep4. The region did not show complete fixation,as a few domestic birds carried a wild-type haplotype.
The number of putative sweeps reaching the ZH p-score threshold of26was highest for the all-domestic comparison:58windows representing21loci passed this threshold.Further genetic and func-tional studies of these loci are well justified because many of them, as well as some that did not reach the significance threshold,may have contributed significantly to chicken domestication.Three putative sweeps had ZH p scores that were more extreme(that is, lower)than that of yellow skin/BCDO2.One was located on chro-mosome1in a non-coding region upstream of SEMA3A,which encodes semaphorin3A,an axon guidance molecule with an essential role in brain development9.The second occurred in a non-coding region160kb upstream of the gene for V-set and transmembrane-domain-containing protein2A(VSTM2A),which is a predicted target-SNARE gene on chromosome2,and the third occurred at the locus encoding thyroid stimulating hormone receptor(TSHR) on chromosome5.We decided to further evaluate TSHR because it had the lowest ZH p score(29.2)and because of the well-established biological significance of TSHR signalling for metabolic regulation and reproduction10–13.The sweep region showed almost complete fixation over a40-kb region(Fig.3).The TSHR region also approached significance for the individual broiler and layer com-parisons,with ZH p scores of4.7and4.9,respectively.Both groups showed complete homozygosity at the TSHR locus but failed to reach the threshold of26because the sweep regions did not cover a full 40-kb window.In the all-domestic comparison,the consistent sweep signal from all eight populations resulted in an extremely low ZH p score even though the region of complete homozygosity across all populations did not cover an entire40-kb window.
We decided to screen eight SNPs from the TSHR region using271 birds representing36populations with geographic origins ranging from Iceland to China(Supplementary Table4).Every domestic chicken tested,representing commercial as well as local populations, carried at least one copy of the sweep haplotype;seven birds were heterozygous for the haplotype and264were homozygous.This is remarkable given the extensive genetic diversity present in the domestic chicken for most parts of the genome.Thus,TSHR may be a domesti-cation locus in chicken,that is,a locus where essentially all individuals of a domesticated species carry a mutant allele.We observed the sweep haplotype at an intermediate frequency in red jungle fowl representing zoo populations(Supplementary Table4),and believe that the most likely explanation for this is that many zoo populations have a history of some hybridization with domestic chicken.
We next searched for candidate mutations that may have been the target for the TSHR sweep and identified a non-conservative amino-acid substitution,namely glycine to arginine at residue558(Fig.3c). This residue is located at the border between transmembrane region4 and the following extracellular loop(Fig.3d).Glycine at this position is conserved among all known vertebrate TSHR sequences and it is almost completely conserved among other members of this family of glycoprotein-hormone receptors(see the Glycoprotein-hormone Receptors Information System;http://gris.ulb.ac.be/).A bioinformatic analysis using DASher14indicated that the glycine-to-arginine substi-tution pushes this residue outwards from the membrane and may therefore influence ligand interaction.Thus,this missense mutation
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is a candidate causal mutation for the TSHR sweep.Currently,we cannot formally exclude the possibility that the identified missense substitution is a slightly deleterious mutation that has hitch-hiked on a linked causative mutation.However,careful examination,includ-ing Sanger-based resequencing of the 40-kb sweep region to close any sequence gaps,did not reveal any strong suspects (GenBank accession numbers GU323554–GU323556).
A possibility is that the domestic TSHR allele confers an advantage as regards increased metabolic activity and growth.However,this is unlikely,because the TSHR locus does not coincide with any of the 13growth loci detected in our previous QTL study of an intercross between White Leghorn and red jungle fowl 15,where the two TSHR alleles are segregating.It is now well established that TSHR signalling between the pars tuberalis,of the pituitary gland,and ependymal cells in the hypothalamus regulates photoperiod control of reproduction in birds and mammals 11–13.The TSHR sweep may therefore be related to a classical feature of domestic animals,namely the absence of the strict regulation of seasonal reproduction found in natural populations 16.We plan to follow up the discovery of the TSHR sweep with functional receptor studies as well as careful phenotypic characterization of our White Leghorn/red jungle fowl intercrosses.
The screen for selective sweeps in populations of commercial broi-lers revealed many loci that make sense in relation to selection for muscle growth (Fig.2c).A region on chromosome 1with strong support contains both the gene for insulin-like growth factor 1(IGF1),which is a candidate gene for growth,as well as the gene for pro-melanin-concentrating hormone (PMCH ),which has important roles in appetite and metabolic regulation 17.IGF1also shows a strong indication of a selective sweep in the layer comparison (ZH p ,25.6;Supplementary Table 3)but not in the all-domestic comparison,as different haplotypes are close to fixation in broilers and layers.A functionally related candidate gene affecting growth traits and with a central role for insulin signalling,insulin receptor (INSR ),also lies within a sweep region.
The sweep at the TBC1D1(TBC1(tre-2/USP6,BUB2,cdc16)domain family,member 1)locus is particularly interesting,because it is located at the major QTL explaining differences in growth between broilers and layers in three independent studies 18–20.Strong further support for the TBC1D1sweep comes from the fact that the sweep haplotype is also fixed in the high and low growth lines (Fig.1).This implies that the sweep took place during the early development of broiler chickens,as the high and low growth lines were established in 1957and have been kept as closed populations since then.TBC1D1has been associated with susceptibility to obesity in humans 21,and a loss-of-function mutation in this gene causes leanness in mice 22.It has recently been shown that insulin-stimulated phosphorylation of TBC1D1is required for the translocation of the main glucose transporter,GLUT4(also known as SLC2A4),to the cell surface of mouse C2C12myoblasts 23.This study implies that billions of broiler chickens around the world carry a mutant TBC1D1haplotype and could be used for in-depth functional studies.It has been proposed that loss of function may be an important factor in rapid evolution,such as occurs during domestication 24.Deleterious mutations may also accumulate as a result of relaxed selection or hitch-hiking during selective sweeps 25.We used the resequencing data to look for two specific loss-of-function mutations:
Layers
c
BCDO2
**SEMA3A/SEMA3D *ECR
ENS:22710
**VSTM2A
ENS:22912
TSNARE1*ECR
TSHR ANK2*ECR
LIPA
ENS:06384SLC16A12ENS:12584
NAT5BAZ2B
*EST
PLOD2PMCH IGF1NUP37C12orf48
ROBO2**VSTM2A
TXNDC10 ENS:19509 ENS:13762
HNF4G TBC1D1PGM2
RCJMB04_8n15BRCA1NBR1
etc.INSR
SIN3B N u m b e r o f 40-k b w i n d o w s
a
Z H p
Z H p
Z H p
EML4
OSGIN1ENS:21325Commercial broilers
*ECR3
MTUS1HNF4G
ENS:25519ENS:22847
AGTR1OSGIN1ENS:21325
BRCA1
NBR1etc.
*ECR
ALS2
MPP4TSHR
TSHR
Figure 2|Selective-sweep analysis of the chicken genome.a ,Distributions of pooled heterozygosity values,H p ,and corresponding Z transformations,ZH p ,for all 40-kb windows (n 546,906).Bins of H p and ZH p are presented along the x axes.m ,mean;s ,standard deviation.b ,Selective sweep at the yellow skin/BCDO2locus 4.Genes in the vicinity of the sweep are shown below the graph.*marks the sweep interval defined using sequence data from all pools of domestic chickens.**marks the 23-kb interval previously associated with yellow skin 4.c ,The negative end of the ZH p distribution presented along chromosomes 1–28.The
horizontal dashed lines indicate the threshold at ZH p 526.Genes residing within 20kb of a window with ZH p #26are indicated by their gene names.The location of TSHR is also
indicated in the plots for commercial broilers and layers,even though ZH p did not pass the threshold of 26.Ensembl genes are denoted ENS:XXXXX,where XXXXX are the last five digits of the Ensembl chicken gene annotation (ENSGALG:11digits).For windows with no gene overlap,the presence of PhastCons evolutionary conserved regions (ECRs)and expressed
sequence tags (ESTs)is indicated with a single asterisk.**indicates a gene candidate close to a window with no genes overlapping 620kb.
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stop-codon mutations and deletions (Supplementary Information and Supplementary Tables 5and 6).We identified almost 1,300dele-tions that were fixed or close to fixation in at least one population.Only 16of these were longer than 6.4kb and none was longer than 67kb (Supplementary Fig.3).We found little evidence that selection for loss-of-function mutations has had a prominent role in chicken domestication.However,we detected seven deletions in coding sequences (Supplementary Table 7),one of which has previously been described as functional and another of which shows strong evidence of function.The deletion in the growth hormone receptor (GHR )gene has previously been reported to be a causative mutation for sex-linked dwarfism 26and has been used in some commercial broiler lines to reduce growth and feed consumption in parental lines.
We also found a novel deletion that removes all but the first exon of the gene SH3RF2(SH3domain containing ring finger 2)(Fig.4a).The deletion is fixed in the high growth line and occurs at a low frequency in the low growth line and in CB-1.SH3RF2lies within a QTL region for body weight detected in a cross between the high and low growth lines 27.We genotyped 400birds from generation F 8of this intercross,which provides a much better mapping resolution
than generation F 2(ref.28).The analysis revealed a highly significant association between the presence of the deletion and increased growth (P ,0.001;Fig.4b).Body weight at 70days for Del/Del birds (600g)was 20%greater than for WT/WT birds (500g).We could take advantage of the fact that the deletion was also present at a low frequency in the low growth line.If this is the causative mutation,it should be associated with the same QTL effect in generation F 2whether it was inherited from an F 0chicken from the high growth line or the low growth line.This provides high resolution in QTL mapping because the lines were crossed after generation 41of the selection experiment,meaning that they are separated by 82generations of meioses,disrupting the associations between the QTL and linked markers.The estimated effects of the deletion haplotype originating from the high growth line were indistinguishable from those of it originating from the low growth line (Fig.4c).This shows that the deletion or a mutation in the very near vicinity must be the causative mutation for the QTL.Expression analysis using hypothalamus messenger RNA revealed SH3RF2expression in the low growth line but not in the high growth line,which is expected because the latter is fixed for the deletion (Fig.4d).The result is of interest as it is well
42444648 (Mb)
00.10.20.3
0.4
b
TSHR GTF2A1 SEL1L DIO2a
c
Gly 558Arg
40-kb windows on chr. 5
0.540
Red jungle fowl TSHR H p d
LR vs LR LR vs BR
BR vs BR RJ vs Dom Ref vs Dom
0.2
0.40.60.810
Identity score
TSHR
WL-A WL-B RIR OS CB-1CB-2High Low RJ Ref
Selective sweep
STON2Domestic chicken Zebra finch Human Macaque Mouse Horse
Domestic pig Dog Cow Frog Cichlid Bass Salmon Catfish
Sea lamprey
42.542.742.943.143.343.543.743.9 (Mb)
SHR GT
Figure 3|Details of TSHR mutation and sweep region.a ,Pooled heterozygosities,H p ,in the all-domestic data set,plotted for 40-kb windows on chromosome 5.The most highly fixed window (grey box)overlaps the TSHR gene.b ,Degree of haplotype sharing in pairwise comparisons among populations.SNP frequencies in individual lines were used to calculate identity scores in 40-kb windows.Greyscale/purple boxes (left)indicate the comparison performed on that row according to the shade/colour assigned to each chicken line (left versus right column).Heat-map colours (right)indicate identity scores.LR,layers;BR,broilers;RJ,red jungle fowl pool;Ref,reference genome haplotype;Dom,domestic chicken;OS,obese strain;High/Low,high/low growth line.c ,A TSHR missense mutation Gly558Arg is highly frequent in domestic chicken.Dashes indicate positions
identical to the red jungle fowl sequence.Polar and positively charged amino acids are green and blue,respectively.d ,Schematic structure of chicken TSHR based on the model provided by the Glycoprotein-hormone Receptors Information System (http://gris.ulb.ac.be/).In the
magnification,the amino acids are coloured according to their properties:blue,basic;
red,acidic;green,polar;grey,hydrophobic.The amino-acid substitution is indicated by the red arrowhead (amino acid 558in UniProt Q3V5M1).
A l l e l e s u b s t i t u t i o n e f f e c t (g )
0Age (days)
B o d y w e i g h t (g )
R e l a t i v e e x p r e s s i o n
b
c
d
Chr. 13:Assembly gaps SH3RF2 (ENSGALT00000011994)18,360,000
18,365,000
18,370,000
18,375,000
18,380,000
18,385,000 (bp)
High-growth-line SOLiD coverage a
repeats
Low-growth-line SOLiD coverage RJ-ref bird SOLiD coverage
04
28425670
Del High Low High Low
Low
Del WT M F M F Figure 4|Characterization of the SH3RF2
deletion.a ,Gene annotation and human protein homology with depth of sequence coverage in the high growth line (top),the low growth line
(middle)and in the reference bird (bottom).The 18,961-bp deletion (red arrow)in the high growth line deletes all but the first exon of SH3RF2.b ,Growth curve for WT/WT,WT/Del and Del/Del F 8birds from a cross between the high and low growth lines.WT,wild-type allele;Del,deletion allele.Error bars,s.e.m.
c ,Estimate
d allel
e substitution effect on body weight in day-70F 2animals,comparing the respective weight gains observed when the
deletion is inherited from high-and low-growth-line parental birds.Error bars,s.e.m.d ,SH3RF2mRNA expression in male (n 53in each line)and female (n 57in each line)high-and low-growth-line chickens.
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established that chickens from the high growth line have a genetic defect in hypothalamic appetite regulation29.
The results strongly suggest that the deletion,eliminating most of the coding sequence of SH3RF2,is the causative mutation for a QTL contributing to the remarkable difference in growth between the high and low growth selection lines.The nature of the mutation,that is, loss of function of a gene that is well conserved among birds and mammals,suggests that the deletion is unlikely to be just a neutral linked marker.SH3RF2encodes SH3domain containing ring finger2 and is expressed in brain and muscle.The high and low growth lines now provide the first animal model with which the functional sig-nificance of this gene may be explored.
The present study casts light on the genetic basis of domestication,but also has implications both for the use of chicken as a model organism for biomedical research and for the application of genomics to practical chicken breeding(Supplementary Information).Chicken was selected for this study because the fairly small genome size(,1Gb)made it easier to achieve sufficient sequence coverage to obtain a reasonable power to detect sweeps,deletions and high-quality SNPs.However, the successful outcome of this approach suggests that it should be applied to other domesticated species as well as to natural populations, where it may reveal the genetic basis for rapid evolutionary adaptations. METHODS SUMMARY
SOLiD sequencing.We prepared libraries from pools of genomic DNA(except for the UCD001reference individual)and sequenced them using SOLiD(ver-sion2was used for all runs except two WL-A runs,for which we used version1) according to standard manufacturer protocols.
SNP detection and analysis.We called SNPs using the Corona Lite pipeline from Life Technologies.To call a SNP,at least three reads with different start sites supporting the non-reference allele had to be present.We called SNPs on each individual line and also by bioinformatically combining the data from multiple pools to improve sensitivity to rare alleles.All reported SNPs are unique sites from the union of all runs.
Selective-sweep analysis.We used allele counts at SNP positions to identify signatures of selection in sliding40-kb windows,for pools of sequence data. For each pool and SNP,we determined the numbers of reads corresponding to the most and least abundant allele(n MAJ and n MIN).For each window in each breed pool,we calculated a pooled heterozygosity score:H p52S n MAJ S n MIN/ (S n MAJ1S n MIN)2,where S n MAJ and S n MIN are the sums of n MAJ and,respec-tively,n MIN for all SNPs in the window.Individual H p values were then Z-transformed as follows:ZH p5(H p2m H p)/s H p.
Detection of deletions and stop codons.We first scanned the genome for putative deletions in each line.A putative deletion was defined as100bp or greater with no read coverage.We then tested all of these regions against coverage by the reference bird to remove those that were uncovered because of sequencing or alignment bias. Full Methods and any associated references are available in the online version of the paper at https://www.doczj.com/doc/ef8489779.html,/nature.
Received22September2009;accepted8January2010.
Published online10March2010.
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body weight in white Plymouth rock chickens.Poult.Sci.75,1168–1179(1996). Supplementary Information is linked to the online version of the paper at https://www.doczj.com/doc/ef8489779.html,/nature.
Acknowledgements Thanks are due to J.Altimiras,J.Dodgson,F.Imsland and S.Kerje for providing genomic DNA samples.We would also like to thank
E.Sonnhammar for help with the bioinformatic analysis of the TSHR sequence,the Uppsala Genome Center for SOLiD sequencing and the Uppsala Multidisciplinary Center for Advanced Computational Science for help with data storage and analysis.This work was supported by grants from the Swedish Foundation for Strategic Research,the Knut and Alice Wallenberg Foundation,the Swedish National Infrastructure for Computing and The Swedish Research Council for Environment,Agricultural Sciences and Spatial Planning.K.L.-T.and O¨.C.are supported by European Young Investigator awards.
Author Contributions C.-J.R.was responsible for the selective-sweep analysis; M.C.Z.was responsible for detection of deletions and stop-codon mutations,and contributed to the selective-sweep analysis and SNP detection;J.E.was responsible for SNP verification and experimental validation of selective sweeps, J.R.S.M.was responsible for experimental validation of deletions and stop-codon mutations;E.S.and T.S.contributed to bioinformatic analysis;M.T.W.was responsible for the phylogenetic analysis;L.J.and M.I.contributed to SNP detection;S.K.and F.H.contributed to the experimental analysis of SH3RF2;F.B. and O¨.C.performed the QTL analysis of SH3RF2;B.B.,M.T.B.,P.J.and P.S.provided biological samples of critical importance;K.L.-T.contributed to the experimental design and analysis;and L.A.designed and coordinated the study.L.A.wrote the paper together with all co-authors,who contributed sections and edited drafts to yield the final version of the manuscript.
Author Information The SOLiD reads have been submitted to the NCBI Sequence Read Archive under the study accession number SRP001870.SNPs reported in this work can be accessed from dbSNP using the query https://www.doczj.com/doc/ef8489779.html,/ projects/SNP/snp_viewBatch.cgi?sbid5?batch?,in which?batch?is each of 1049678,105005–7,1050009,1050013–4,1050016,1050018–9,1050029–50. Data generated by Sanger-based resequencing of the TSHR region,putative deletions and introduced stop codons have been submitted to GenBank under the accession numbers GU323512–GU323556.Reprints and permissions information is available at https://www.doczj.com/doc/ef8489779.html,/reprints.This paper is distributed under the terms of the Creative Commons Attribution-Non-Commercial-Share Alike licence,and is freely available to all readers at https://www.doczj.com/doc/ef8489779.html,/nature.The authors declare competing financial interests:details accompany the full-text HTML version of the paper at https://www.doczj.com/doc/ef8489779.html,/nature.Correspondence and requests for materials should be addressed to L.A.(leif.andersson@imbim.uu.se).
NATURE|Vol464|25March2010LETTERS
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METHODS
Animals.We included genomic DNA samples from the following chicken populations.Four layer lines were sampled:eleven males from White Leghorn line13(WL-A)developed at the Swedish University of Agricultural Sciences30and previously used for QTL mapping experiments15;eight males from a commercial White Leghorn line(WL-B);ten males from the obese strain (OS)established in1955from a White Leghorn line as a model for autoimmune thyroiditis31;and eight males from a commercial Rhode Island Red population (RIR;Hubbard ISA)collected as part of the AvianDiv project32.Four broiler lines were sampled:ten males from a commercial broiler line(Ross308, denoted CB-1here),ten females from a second commercial line(CB-2),main-tained by Hubbard ISA and collected by the AvianDiv project32;and seven males and four females each from the high and low growth selection lines,both established from White Plymouth Rock chickens in195729and used in previous QTL mapping experiments27,33.Eight males representing two different zoo populations of red jungle fowl(RJ)were pooled.Finally,the single RJ female from the partly inbred UCD001line used to generate the chicken genome sequence8was also included.
SOLiD sequencing.Libraries were prepared from pools of birds(except the UCD001reference individual)and sequenced using SOLiD,version2(except for two WL-A runs,for which we used version1),according to standard manu-facturer protocols.Reads were aligned in colour space to the reference assembly (version2.1,Washington University)using the MAPREADS program allowing for up to three mismatches(including‘valid adjacent’changes as a single mismatch)and no indels.Only reads aligning uniquely in the genome were retained.
SNP detection and analysis.SNPs were called using the Corona Lite pipeline from Life Technologies.To call a SNP,at least three reads with different start sites supporting the non-reference allele had to be present.We called SNPs on each individual line and also by bioinformatically combining the data from multiple pools to improve sensitivity to rare alleles.All reported SNPs are unique sites from the union of all runs.Following determination of all unique variant sites, we in silico genotyped all variant sites in all lines using custom PERL scripts,to compare all uniquely aligned reads in colour space to both the reference and variant alleles to count reference and variant alleles observed in each line. Genetic differentiation was measured between lines with pairwise fixation index(F ST),using an estimator introduced in ref.34.This statistic was calculated across all SNPs identified in any line within the assembled chromosome sequences(that is,SNPs assigned to the‘_random’and‘Un’sequences were excluded).Then a phylogenetic tree was constructed from these estimates using the neighbour-joining method implemented in PHYLIP35.
SNP validation.A VeraCode GoldenGate assay(Illumina)was designed target-ing384SNPs that were called in the White Leghorn/red jungle fowl comparison. All SNPs were located in putative selective sweep regions identified in an initial screen for chromosomal regions showing a high degree of homozygosity.A total of271domestic chickens representing36populations and51red jungle fowl from a number of zoo populations were genotyped using the standard protocol provided by Illumina.The GoldenGate assays were read using a BeadXpress Reader(Illumina)and data were analysed on the GENOMESTUDIO V2009.1 software(Illumina).To estimate the false-negative rate of our SNP-calling pipe-line,the sequence from the yellow skin allele4(GenBank EU334162)determined by classical Sanger-sequencing was used.By comparing the sequence against the reference genome sequence,a total of175SNP positions were detected.Those SNP positions were cross-referenced with the SNP positions called in the all-domestic comparison.
Estimation of total SNP errors.All calls made at known SNP sites on the Z chromosome(ascertained in lines other than the reference bird)were reviewed and the number of valid base calls of each type made at that position in the reference bird was counted.For all sites with two or more calls,we assumed that any minority calls were errors(rather than using the reference base,to avoid counting errors at miscalled reference bases).As expected given that the Z chromosome in the reference female is hemizygous,we predomi-nantly saw positions with two or three reads.We took the single-read,per-position error rate to be that seen at three reads of coverage(0.00644).We note that this includes both sequence detection errors and artefacts intro-duced by alignment errors and is approximately ten times worse than the manufacturer’s specification of rates of accuracy after dibase correction (99.94%);independent assessment of single-base accuracy from invalid colour changes suggests that raw sequencing accuracy for these runs was very close to the manufacturer’s specification.Because errors should be random,it was assumed that one-third of them would represent each incorrect base,and we thus computed for each depth of coverage in the genome the probability of seeing three or more of any given erroneous base.These probabilities were all multiplied by the total number of bases seen at each depth and summed over all depths.
Selective-sweep analysis.Allele counts at identified SNP positions were used to identify signatures of selection in sliding40-kb windows with a step size of20kb for three pools of sequence data(breed pools):all eight domestic lines,the two commercial broiler lines(CB-1and CB-2)and three layer populations(WL-A, WL-B and RIR).At each detected SNP position,we counted the numbers of reads corresponding to the most and least frequently observed allele(n MAJ and n MIN,respectively)in each breed pool.This was done even if a particular SNP had not been originally detected by reads from the particular breed pool where the selective-sweep scan was performed.To prevent windows containing very few SNPs from adding spurious fixation signals,we omitted seven windows where only1–10SNPs had been detected and analysed46,906windows along chicken chromosomes1–28represented in the version2.1draft assembly.For each window,we calculated the pooled heterozygosity,H p,values using the formula H p52S n MAJ S n MIN/(S n MAJ1S n MIN)2,where S n MAJ and S n MIN are breed-pool-specific sums of n MAJ and,respectively,n MIN counted at all SNPs in the window.The distributions of H p values resembled normal distributions(Fig.2a), and we therefore transformed the H p values into Z scores:ZH p5(H p2m H p)/ s H p.The Z transformation allowed us to place the three breed pools into the same framework because ZH p values indicate the number of standard deviations by which H p deviates from the mean.We applied a threshold of ZH p#26for putative selective sweeps because windows below this threshold represent the extreme lower end of the distribution(Fig.2a).
Calculation of identity scores.We calculated identity scores,IS,to visualize haplotype sharing in pairwise comparisons at the TSHR locus(Fig.3b).For each identified SNP,we determined the fraction of reads that corresponded to the reference genome allele,F,in each chicken line.The IS values of individual SNPs were then calculated as IS512(j F line12F line2j),with SNPs assessed only if at least one read was obtained in each line.The IS value for a window was the mean of all SNP IS values observed in the window for a specific comparison.
QTL analysis.The phenotypic effect of the SH3RF2deletion was estimated in two ways.First,the genotype–phenotype map for the three genotypes(Del/Del, Del/WT and WT/WT)was estimated without accounting for the line origin of the alleles and accounting for the observed allele frequencies using the R package NOIA36,37,version0.92.Second,the effect of the deletion was estimated inde-pendently within the low growth and high growth lines by computing the IBD (relationship)matrix following ref.38,under the assumption of three subsets of alleles in generation F2(Del originating in F0birds from the high growth or low growth lines and wild type(WT)always originating in F0birds from the low growth line).
Detection of deletions and stop codons.We first scanned the genome for putative deletions in each line.A putative deletion was defined as100bp or greater with no read coverage.We then tested all of these regions against coverage by the reference bird to remove those that were uncovered because of sequencing or alignment bias.We computed the binomial p value of an N:0split of reference and line reads given the chromosomal total reference:line ratio.To correct for testing,1,000,000putative deletions in all lines,we required a P value of,1028 to consider a region deleted.However,if a putative deleted region reached this significance threshold in one line,a P value of,1025was considered sufficient to call the presence of an overlapping deletion in other lines.Then we merged by single linkage all overlapping deletion events in multiple lines,on the assumption that such events were likely to be identical.Finally,we merged runs of consecu-tive deletions that occurred in the same line(s)if the sum of deleted bases was at least90%of the total span length;manual inspection revealed that such events were usually incorrectly split because of sequences that attracted spurious read placement,or possibly because the line was not100%fixed for the event.Two such events overlapped genes and were successfully validated as single deletions, supporting this‘bridging’.Because of the absence of W sequences in male birds and the large amount of unplaced W sequences,the W chromosome and all random and unplaced chromosomes were excluded from this analysis.To pre-vent regions of unusually high coverage in the reference bird from causing false-positives,we ignored reads in any line overlapping any region that had coverage in any line exceeding that expected given all of our sequencing(Poisson P#0.05, Bonferroni corrected for sites observed across all lines).
To detect stop codons,the Ensembl gene set was filtered to include only models that made a complete protein product of$100amino acids.We then computed the impact of the alternate allele of every detected SNP on its in-frame codon for each transcript overlapping it.If either the reference or the alternate codon was a stop,it was retained for manual review.During manual review,we discarded any putative stop variant if the transcript failed to show homology to any known protein or if the variant codon lay outside a region of conservation in the alignment and was not supported by chicken EST evidence.
Validation of loss-of-function mutations.Putative deletions or introduced stop codons were amplified using approximately20ng of genomic DNA from individuals taken from the appropriate pool in10-m l reactions containing 10mM Tris-HCL(pH8.3),50mM KCl,2.5mM MgCl2,0.2mM dNTP,1m M each of forward and reverse primer and0.5U AmpliTaq Gold(Applied Biosystems).Validation of products was performed by direct sequencing using BigDye Terminator v3.1chemistry(Applied Biosystems)and DNA sequences were aligned and edited using CODONCODE ALIGNER(version 3.0.2, CodonCode).The true break points of validated deletions that affected coding sequencing were used to design multiplex PCR assays.These reactions were amplified as above,but with1m M of each multiplex primer(m1,m2and m3) and visualized on2%agarose gels.Multiplex assays were also applied to a diversity panel(Supplementary Table9)to assess the prevalence of the mutation in a global setting.All primers were designed in PRIMER339(version0.4.0)and are given in Supplementary Table9,and new sequences have been deposited in GenBank(accession numbers GU323512–GU323553).
SH3RF2expression study.We dissected hypothalamus from four-day-old birds from both the high growth and low growth lines(three male and seven female chicks from each line,for a total of20samples).RNA was isolated with TRIzol (Invitrogen)and purified with RNeasy Mini Kit(Qiagen).The quality of the total RNA was checked with the Agilent2100Bioanalyser(Agilent Technologies) and the RNA samples were frozen at270u C until https://www.doczj.com/doc/ef8489779.html,plementary DNA synthesis from total RNA and two-step quantitative PCR were performed as described previously40.Briefly,quantitative PCR with reverse transcription was performed using the iQ SYBR Green Supermix(Bio-Rad Laboratories)in combination with the MyiQ Single-Colour Real-Time PCR Detection System (Bio-Rad Laboratories),according to the manufacturer’s protocol.Primers were designed with PRIMER EXPRESS software(version1.5,Applied Biosystems) and are listed in Supplementary Table9.The collected data were analysed using the2{DD C T method41in comparison with the average of the four-day-old high-growth-line male expression level,and all results were normalized to the chicken b-actin gene.
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西门子伺服电机选择手册，SINAMICS S120是一种集V/F、矢量控制和伺服控制于一体的新型驱动控制系统。普通异步电动机不能控制转矩，也不能控制三相异步电动机。 S120系列驱动与伺服电机选型手册第1部分：典型结构的多轴驱动控制单元电机模块与通用直流母线电源模块。带起动机（或scout）和SIMATIC manager软件或s7-300400的书本式柜式PC典型配置图，SIMOTION O/D/P 24 V DL说明：1：主控制模块cu320 2：电源模块SIM 或ALM+24 V电源3：单轴电机模块4：两轴电机模块234电源线终端模块驱动Cliq编码器反馈信号线选项板电抗器功率滤波器传感器模块无编码器电机运动控制，带drivc Cliq接口西门子（中国）自动化传动集团有限公司生产机械SINAMICS S120系列，选自《S120驱动与伺服电机选型手册》第1章多轴传动概述。Sinamics120是一种集V/F、矢量控制和伺服控制于一体的新型驱动控制系统。它不仅可以控制普通的三相异步电动机，还可以控制步进电动机、转矩电动机和直线电动机。其强大的定位功能将实现进给轴的绝对和相对定位。2007年6月发布的DCC（drive control chart）功能将实现逻辑、计算和简单处理功能。SINAMICS S120产品包括：用于普通直流母线的DCAC逆变器和用于单轴的ACAC逆变器。具有公共直流母
线的DC/AC逆变器也称为多轴驱动。它的结构是电源模块和机器模块分开。电源模块将三个交流电整流成540V或600DC，并将电机模块（一个或多个）连接到直流母线。特别适用于多轴控制，特别适用于造纸、包装、纺织、印刷、钢铁等行业。优点是电机轴间能量共享，接线方便简单●单轴控制交流变频器，俗称单轴交流传动，其结构是功率模块和电机模块的组合，特别适合单轴速度和定位控制。本书第一部分包括第1至4章，主要介绍多轴交流传动。第二部分包括第五章至第八章，主要介绍单轴交流传动。第三部分包括第九章，主要介绍电机电缆和信号电缆。第四部分包括第10章，介绍了同步和异步伺服电机的指令数据。第五部分，包括第11章，简要介绍了运动控制系统的指令数据。这本书中的技术资料基本上是英文的。详情请参阅英文原文。西门子（中国）有限公司自动化与传动集团运动控制部生产的机械系列S120系列，源自《S120驱动与伺服电机选型手册》第二章。功率模块是我们通常所说的整流器或整流器/反馈单元。它将三相交流电整流成直流电，并为每个抑制模块（通常称为逆变器）供电。具有反馈功能的模块还可以向电网提供直流电。根据是否有反馈功能和反馈方式，将功率模块分为以下三类：基本线路模块：整流单元，但无反馈功能。智
比喻与拟人的区别 现代文阅读考点与答题技巧-拟人拟物的表达效果 比拟的赏析要点 1、定义： 比拟是把甲事物模拟作乙事物来写的修辞方式。包括把物当作人来写（拟人）；把人当作物来写（拟物）和把此物当作彼物来写（拟物）几种形式。事实上，前一种形式是把事物“人化”，后两种形式则是把人“物化”或“把甲物乙物化”。 2、种类： ①、拟人。例如：女人坐在小院当中，手指上缠绞着柔滑修长的苇眉子，苇眉子又薄又细，在她怀里跳跃着。 ②、拟物。例如：指导员讲得真来劲儿．嘎子竖起耳朵听。 3、比拟的作用： 第一,比拟的主要效果是使表达形象生动.比拟可以让静的变成动的,让 死硬呆板的变成活泼和有生气的,让无性格的变成有性格的,让抽象的变成具体形象,活灵活现的.客观事物经过人们合理的属性转移和合乎规律的创造性想象,而 变得富有艺术魅力. 比如: 沙果笑得红了脸,西瓜笑得比蜜甜,花儿笑得分了瓣,豌豆笑得鼓鼓圆.《红旗歌谣》 将植物"沙果""西瓜""花儿""豌豆"等都人格化了,形象生动地描绘出了丰收的景象. 第二,通过比拟,还可以表现人们的想象力,思想倾向和感情色彩,并创造某种意境,给人以强烈的感染力. 例如 秦淮河失去了往日的欢笑,莫愁湖发出了撕胆的哭声.(张天明《按照人民的命令》) 用拟人方法描写了中国人民失去总理的悲哀,连江河湖泊也发出了悲哀的哭声,表达出了人民对周恩来同志无比热爱的真挚感情. 4、总体把握 同比喻类似，把握“比拟”类修辞的表达效果时，要先弄清楚本体和拟体，然后分析拟体的特点，再结合这个特点来考虑作者所要表现的本体的特征。 5、分类指导 第一拟人 把事物当成人来写，赋予人的思想、感情、活动，这样的修辞方法就叫拟人。 人具有会说话,会思想,会劳动,会创造和富有感情的本质特点,人类对自己的这些本质特点最为熟悉,最为理解,最易接受,最易产生共鸣.为了表达的需要,将人的本质特点转移于其他事物,让它们具有人的某些特点,可以将事物描写得具体,生动,形象,使人感到亲切,容易受到感染. 以动物拟人： 例如 一只探险的蜜蜂正绕着布满的柳树枝头的金色的花朵嗡嗡着.看不见的云雀在天鹅绒般的绿油油的田野和盖满了冰的,收割后的田地上颤巍巍地歌唱着;田凫在那积满了塘水的洼地和沼泽上面哀鸣;鹤和鸿雁高高地飞过天空,发出春的叫喊.脱落了的毛还没有全长起来的家畜在牧场上吼叫起来了;弯腿的小羊在它们那掉了毛的咩咩地叫着的母亲身边跳跃;……真正的春天已经到来了.②(托尔斯 泰《安娜·卡列尼娜》) [简析]上述文字具体地,有层次地描写了春天给动物带来的变化.作者将动物人格化,赋予它们以人的品格.蜜蜂在"探险",云雀在"歌唱",田凫在"哀鸣",鹤 和鸿雁发出"叫喊",小羊在"母亲"身边跳跃.作者将这些动物写得栩栩如生,画面洋溢着春天到来的蓬勃生机.从而让人感受到作者心中的安慰,希望和信心.
修辞手法 具体有比喻：可分为：明喻、暗喻、借喻 有白描，比拟（又名比体），衬托（又名反衬、陪衬），倒装，顶真（又名顶针、联珠），对比，对仗（又名对偶、队仗、排偶），反复，反问，反语 有互文，借代，设问，排比，夸张，双关，用典，引用，移用，象征，镶嵌，通感。 1 常用修辞作用特点： 1．比喻： 作用：将表达的内容说得生动具体形象，给人以鲜明深刻的印象，根据事物的相似点,用具体、浅显、常见的事物对深奥生疏的事物解说，即打比方，帮助人深入理解。 比喻的三种类型：明喻、暗喻和借喻： 类别特点本体比喻词喻体例句 明喻甲像乙出现像、似的、好像、如、宛如、好比、犹如出现那小姑娘好像一朵花一样 暗喻甲是乙出现是、成为出现那又浓又翠的景色，简直就是一幅青山绿水画 借喻甲代乙不出现无出现地上射起无数的箭头，房顶上落下万千条瀑布。 2．比拟： 借助丰富的想像，把物当成人来写，或把人当成物来写，或把甲物当成乙物来写。 作用：能启发读者想像，令文章更生动。 比拟分为拟人和拟物 （1）拟人： 把物当做人写，赋予物以人的思想、感情、活动，用描写人的词来描写物。 作用：把禽兽鸟虫花草树木或其他无生命的事物当成人写，使具体事物人格化，语言生动形象。 例句： 1.桃树、杏树、梨树、你不让我，我不让你，都开满了花赶趟儿。 2.感时花溅泪，恨别鸟惊心。《春望》杜甫 3.太阳的脸红起来了。《春》朱自清 （2）拟物 ①把人当作物，或把此物当作彼物来写 例句 1.人群不顾一切，涌了上来。 2.在群众的呼喝声中，那个恶霸夹着尾巴逃跑了。 ②把甲事物当成乙事物来写。 例句 1.火山发出一声咆哮。 2.月光如流水一般，静静地泻在这一片叶子和花上。（《荷塘月色》朱自清） 3．夸张： 对事物的性质，特征等故意地夸张或缩小。 作用：提示事物本质，烘托气氛，加强渲染力，引起联想效果。 类别特点例句 扩大夸张对事物形状、性质、特征、作用、程度等加以夸大柏油路晒化了，甚至铺户门前的铜牌好像也要晒化 缩小夸张对事物形象、性质、特征、作用、程度等加以缩小只能看到巴拿大的一块天地 超前夸张把后出现的说成先出现，把先出现的说成后出现她还没有端酒怀，就醉了。 4．排比： 把三个或以上结构和长度均类似、语气一致、意义相关或相同的句子排列起来。 作用：加强语势、语言气氛，使文章的节奏感加强，条理性更好，更利于表达强烈的感情（表达效果）。
第一方位 福特汽车公司由亨利·福特先生创立于1903年，福特汽车公司生产出世界上第一辆属于普通百姓的汽车——T型车，世界汽车工业革命就此开始。1913年，福特汽车公司又开发出了世界上第一条流水线，缔造了一个至今仍未被打破的世界记录。福特先生为此被尊为“为世界装上轮子”的人。 车头：动感圆润的车头造型，线条饱满、棱角分明。突出的发动机罩线，不仅使车身显得更为强壮，还保证满足最新的行车安全要求。无骨雨刷的运用更是可以在大雨天气为我们开启明亮的视线，而且无骨雨刷经久耐用，噪声小，刷的非常干净，让我们行车跟放心提高安全系数。风雅大气的梯形下格栅通过一个较小的镀铬的上格栅取得平衡，使车头看起来力量感十足，更有一种独特的爆发了，让人有种驾驶的冲动。大灯从视觉上区分开了三厢车型和两厢车型。例如，两厢系列的大灯后盖是黑色的，而在三厢系列上是镀铬的。看起来都炯炯有神，非凡不同给人以无比的犀利质感，显示车主年轻非凡的品味和独特的个性。除了舒适型外，2011款福克斯其他车型同时同时还配置了“Follow Me Home送你回家”功能，在熄火后，还能持续照亮回家的路。福克斯保险杠材质运用了高性能复合材质耐撞力强可以很好的保护车辆所受到的冲击和撞击。而且可以承受匀速15公里/小时的撞击力。 第二方位 Duratec高效能发动机：打开发动机舱，展现在眼前的是排列整齐，布局合理的机舱，清晰细致。体现福特以人为本的设计理念。高效能发动机，当发动机转速到6000rpm时能达到一个91kw的功率，转速到4000rpm时能达到一个161n.m 的扭矩。全铝合金设计的发动机，减少不必要的重量，散热性更好。 Duratec发动机低转速、高扭力的特征明显，在2000转/分时就爆发出90%的扭力输出。这种低转速时的大扭力输出有利于汽车在起步与之后的加速，利于车主提早换档，可以进一步提升福克斯在油耗方面的经济性。福克斯搭载了动力充沛且燃油效率优秀的Duratec-HE全铝合金反置式发动机，配有塑钢等长进气歧管及可变惯性进气系统(VIS)，可提高进入汽缸的空气含氧量，大幅提升燃烧效率，从而达到降低油耗的目的。2011款福克斯提供3年10万公里的保修服务政策，同级车最长保修服务政策。同时提供24小时道路救援。 福特福克斯WRC赛车是征战全球无数赛事的冠军车型，在2006和2007年度的“世界汽车拉力锦标赛”(WRC)中，福克斯赛车凭借其出众的性能表现，为福特车队连续赢得冠军头衔。而在国内的“全国汽车场地锦标赛”(CCC)上，长安福特车队驾驶的福克斯赛车同样不负众望，一举夺得“2007全国汽车场地锦标赛”年度总冠军、“2008年全锦赛”北京站冠亚军。 第三方位 车身侧面：在车的侧面，具有强烈视觉冲击力的腰线贯穿车身前后，使得车辆具有了新的流畅轮廓。车的侧身线条看上去简洁有力。当危难发生时，周延设计的安全车辆，必须要考虑到车身结构的完整与安全性，以有利于乘员救援与脱离的
比喻句的特点和应用 荷叶像一把小伞 比喻，就是打比方。也就是说用浅显的、大家比较熟悉的事物来比喻抽象的、深奥的、人们比较陌生的事物。它是利用两种不同种类的事物之间的某点相似来进行说明或者描写。 一般说来一个比喻句包括三个部分：本体、喻体和比喻词。通常把被比的事物叫作“本体”，把拿来作比的事物叫作“喻体”，把用来联系“本体”和“喻体”的词语叫作“比喻词”。 比喻有三种类型：明喻、暗喻、借喻。三年级主要运用的是明喻，明喻就是明显的打比方，句子的格式是“甲像乙”，在表达时，本体、喻体、比喻词都出现。明喻常用的比喻词是：“像”、“好像”、“像……似的”、“仿佛”、“如同”等等。如：“孔雀那美丽的尾巴抖动着，像一把五彩洒金的大扇子。”本体：孔雀那抖动着的美丽的尾巴，喻体：五彩洒金的大扇子，比喻词：像。 2．比喻句和非比喻句的区别。 在阅读中，我们常常碰到一些句子，句中虽然也有“像”、“好像”等词语，但不是比喻句，这些非比喻句成了迷惑我们判断真正“比喻句”的敌人。 要牢记不能将比喻词语作为判断比喻句的主要依据，主要应分析句子中是否存在比喻关系。如：“他画的荷花就像刚从湖里摘来的一样。”“画的荷花”和“从湖里摘来的荷花”之间只是简单的像，不是比喻。又如：“猫头鹰的耳朵很特别，好像一对立起来的猫耳朵。”“猫头鹰的耳朵”和“猫耳朵”之间是事实上的相像，不是比喻。而“树叶在空中飞舞，像蝴蝶一样。”用“树叶”(本体)和“蝴蝶”(喻体)两种本质不同的事物，在“空中飞舞”的样子很相似来作比，它们之间用“像”(比喻词)来连接，此句是比喻句。通过比较，我们应该更清楚地明确比喻句具备以下两个特点：(1)句中有本体、喻体、比喻词三个部分。 (2)句中本体、喻体必须是两种不同种类的事物，而且有相似之处，存在着比喻关系。典型例题 1．仿照例句，标出下列比喻句中的本体、喻体和比喻词。 例：弯弯的月亮好像一条小船。 (本体) (比喻词) (喻体) (1)美丽的彩虹像一座弯弯的长桥。 ( ) ( ) ( ) (2)黄澄澄的柿子像一盏盏小灯笼挂满了枝头。 ( ) ( ) ( )
西门子选型手册 16ES7?212-1AB23-0XB0CPU（8I/6O）晶体管输出 26ES7?212-1BB23-0XB0CPU??(8I/6O）?继电器输出 36ES7?212-1AB23-0XB8CPU（8I/6O）晶体管输出?CN 46ES7?212-1BB23-0XB8CPU??(8I/6O）?继电器输出?CN 56ES7?214-1AD23-0XB0CPU（14I/10O）晶体管输出 66ES7?214-1AD23-0XB8CPU（14I/10O）晶体管输出?CN 76ES7?214-1BD23-0XB0CPU（14I/10O）继电器输出 86ES7?214-1BD23-0XB8CPU（14I/10O）继电器输出??CN 96ES7?214-2AD23-0XB0CPU224XP（14DI/10DO，2AI,1AO）?晶体管输出? 106ES7?214-2BD23-0XB0CPU224XP?（14DI/10DO，2AI,1AO）继电器输出116ES7?214-2AD23-0XB8CPU224XP?（14DI/10DO，2AI,1AO）晶体管输出126ES7?214-2BD23-0XB8CPU224XP?（14DI/10DO，2AI,1AO）继电器输出136ES7?216-2AD23-0XB0CPU??(?24I/16O?)?晶体管输出 146ES7?216-2BD23-0XB0CPU（24I/16O）继电器输出 156ES7?216-2AD23-0XB8CPU??(?24I/16O?)?晶体管输出?CN 166ES7?216-2BD23-0XB8CPU（24I/16O）继电器输出?CN 176ES7?221-1BF22-0XA08点24VDC输入 186ES7?221-1BF22-0XA88点24VDC输入?CN 196ES7?221-1BH22-0XA016点24VDC输入 206ES7?221-1BH22-0XA816点24VDC输入?CN 216ES7?222-1HF22-0XA08点继电器输出
嘉年华六方位介绍 一、品牌篇 福特是当前世界一流品牌，已经有一百多年的历史，这款嘉年华是第六代嘉年华，嘉年华从第一代就很成功，到第五代就已经累计销售了1000多万辆。而2009年中国汽车累计产销也才突破1300万辆。通过一代代不断完善和改进，推出了现在的第六代嘉年华，它上市前经历了350万公里的路试，所以说性能绝对是一流的。 二、车身面 1、车正面 嘉年华造型非常动感，整车线条很流畅，风阻系数只有0.28，在所有同级车型中，是最低的，这说明嘉年华开起来不仅稳，油耗肯定也很理想。前挡风玻璃是超大型，超强绿色隔热玻璃，视野非常好。还采用同级车很少用的无骨雨刷，寿命更长，噪音更低。前保险杠是强化保险杠，15公里时速内撞击不变形。 2、车侧面 安全是福特一直以来的优势，嘉年华更是如此，车身采用大量的特种钢制，像保障安全的AB柱更是采用硼钢材料。硼钢是用于飞机上的特种钢材，抗压性是普通钢材的2倍多，同级车中他是唯一采用硼钢的，并且车身关键部位采用激光焊接，所以他的安全达到了同级车中少有的欧洲五星级标准，可以说是固若金汤。 3、车后部 嘉年华后部做的也非常精致，与前脸完美搭配，顶部还安装了尾翼，好处是他能保持高度行驶时车身的稳定性。后雨刮也设计的非常人性化。前雨刮器打开挂入倒档时前刮器也能同时开启。 4、车底部 嘉年华采用福特特有C3P加强赛车型底盘，它最大的特点是在高速行驶及过弯道时非常稳定，并且地盘上还装配了它同级车中没有的三根加强横梁，提高了底盘的刚性和稳定性，悬架采用前麦菲逊独立后半独立悬挂。我们的轮胎胎宽时尚型是185，运动型是195，这就让嘉年华在行驶的时候抓地性好，刹车好，高速行驶是很稳。同级车大多采用的都是175的轮胎， 三、车内篇 1、站在车门：嘉年华车内的设计和外形一样非常动感时尚，你可以感受一下各个细节也是做得非常精致，我们的钥匙是折叠式的，显得美观又很有档次，并且钥匙内带有密码防盗芯片，内设的防盗密码是每两个月自动调整的，所以说它的防盗性非常好。 2、进入副驾驶座位：我们这个车不仅视野非常开阔，车内空间也非常宽裕，独特的桶型作业的包裹性非常好，就算高速过弯身体也不会倾斜。仪表与方向盘也都是运动型设计，仪表盘是自带发光功能的，非常漂亮。车的加速和操控性都非常好，手握着动感的方向盘，有着开跑车的感觉。最值得介绍的是这款车的是人车互动的多功能显示屏，是同级别车中所没有的，他的功能非常强大，显示音响，空调，行车，车辆状况，维修保养，故障六大信息，让你都一目了然，既方便又安全。另外，显示屏设计在上方位置，让你在了解信息的同时目光不会离开路面，保障了安全驾驶。嘉年华的面板设计也是非常时尚，整体造型很像变形金刚。音效也非常好，MP3可以直接连到车上，非常方便。车内
比喻句的特点和作用 比喻有很多很好的表达作用，它可以把未知的事变成已知的，把深奥的道理说得浅显把抽象的说得具体，把平淡的事物说得很生动。但如果比喻运用不当，反会弄巧成拙，闹出笑话来。那么，怎样正确地运用比喻呢? 首先，我们在平时对事物观察要细致全面。比喻句中的本体和喻体之间必定存在着可比性，而这可比性又必定是这两者的主要特点，因此，我们观察要细致，思考要全面，抓住事物的本质特点，选择最富可比性的喻体。千万不能草率从事，随便拿来就用，这样只会笑话百出。其次，比喻不仅要贴切，还要易懂。有这样一句比喻句：我今天买了一支钢笔，样子跟潜水艇似的，头尖尖的。这里的“钢笔”是我们常见的，而“潜水艇”倒是大家不太熟悉的。这样的比喻就不太好，达不到运用比喻句的目的。再次，使用比喻句还要注意思想感情的正确性。例如：从走廊的那一头，走出白求恩大夫，记者们像捕获野兽似地扑上前去，照相机的闪光灯不停地闪烁着。用“捕获野兽”来比喻记者们围住白求恩，显然是极不恰当的。 最后，写完一句比喻句，还要仔细看看句子前后的搭配是否确切。如“小河像飘动的绸带”，这一句把“小河”比作“绸带”，是完全可以的。问题在“飘动的绸带”，因为这样一来，使人感到这绸带是飘在空中的，那用来比喻“小河”自然是不恰当的了。因此，只注意比喻物和被比喻物搭配妥当还不够，还要注意其他词语的搭配，否则也会出病句。 这样看来，要写好比喻句，并不是一件易事。但只要你能仔细观察，认真思考，善于动脑，一定能用比喻句使笔下的文章生动、形象、富有感染力。 (1)比喻的特点及作用 比喻就是“打比方”。即抓住两种不同性质的事物的相似点，用一事物来喻另一事物。比喻的结构一般由本体(被比喻的事物)、喻体(作比方的事物)和比喻词(比喻关系的标志)构成。构成比喻的关键：甲和乙必须是本质不同的事物，甲乙之间必须有相似点，否则比喻不能成立。比喻的作用主要是：化平淡为生动;化深奥为浅显;化抽象为具体;化冗长为简洁。 (2)比喻的种类 ①明喻。典型形式是：甲像乙。本体喻体都出现，中间用比喻词“像、似、仿佛、犹如”等相联结。例如：收获的庄稼堆成垛，像稳稳矗立的小山。” ②暗喻。典型形式是：甲是乙。本体喻体都出现，中间没有比喻词，常用“是”、“成了”、“变成”等联结。例如：马克思主义和中国革命的关系，就是箭和靶的关系。 ③借喻。典型形式是：甲代乙。不出现本体，直接叙述喻体。但它不同于借代。借代取两事物相关点，借喻取两事物的相似点。例如：放下包袱，开动机器。 ④博喻。连用几个比喻从不同角度，运用不同的相似点对同一本体进行比喻。例如：层层的叶子中间，零星地点缀着些白花，有袅娜地开着的，有羞涩地打着
新福克斯 2012-4月23号，新福克斯亮相北京车展，时尚的外观，优秀的工艺，赢得了我们广大消费者的一致好评。新福克斯传承福特百年精湛的技术与血统，荟萃前所未有的璀璨科技，当你启动他时，不仅是车，而是一段令人过瘾的驾驭快感。全新的流线设计，后掠式的前大灯，z型的车身线条，环绕式尾灯，处处彰显着无限动感与激情。前进气格栅主动关闭系统，不但能让发动机保持一个最佳的工作温度，而且节能节油。前档声学隔音玻璃，隔音效果优越，搭配蝶式无骨雨刷，让你的视野更加宽阔，还能加热除雾除霜，无论是冰天雪地都能轻松扫除您的障碍。然而，0.295的超低风阻系数，更把新福克斯推向了一个新的里程碑。 新一代福克斯搭载全新2.0GDI缸内直喷发动机，动力澎湃、充沛，缸内高压直喷技术，可实现燃油充分燃烧，让每一滴燃油都用得其所。与6速手自一体双离合的完美结合，让你一路飞奔驰聘，感受着171匹马力带来的无限激情。而百公里油耗却仅为6.8升，超高的工作效率，优异的燃油经济性，这无疑给我们车主，给广大消费者、特别是日益上涨的油价，都交上一份满意的答卷，这就是福特！一个肩并着历史使命和社会责任感的品牌。 自动折叠外后视镜，集成了电动调节、除雾除霜及转向等功能，镜片上面的盲点信息系统，更是贴身保镖，时刻提醒后方车辆的到来，避免盲区带来的潜在危险，时刻保证您的行车安全。新福克斯车身均采用进口硼钢材质，热成型及激光焊接技术，把新福克斯打造成如同装甲车一般的坚硬，无论是A柱到B柱还是超高强度的门槛踏防撞踏板，都为车上的人员树起一面强有力的墙壁，时刻呵护着车上人员的安全。我们的五次元安全：从安全驾驶、安全回避，到安全损控、安全防护，再到安全脱离，‘安全’两字，是我们赋予它的最高肯定。 新一代福克斯底盘采用了世界先进的技术平台，研发出适合中国错综复杂的道路情况，无论冰天雪地，高原戈壁，还是南方的潮湿泥泞，它都能让你一路轻松驰聘，应对自如。空腔注蜡的底盘，不单增加强度，而且防腐降噪，更加适合南方的天气。205的宽胎，动感的轮毂造型，抓地力更强，胎噪更低，制动效果更佳。带副车架的后多连杆独立悬挂，不仅安全舒适，还大大提高对车身的承载力，无论抗侧倾，还是高速的稳定性，都是同级中遥遥领先。 时尚饱满的后尾组合，洋溢着都市活力的气息，宽大的行李箱，灵活的后排，更加方便出门旅行。高密度6层聚乙烯防爆油箱，安全可靠，滴油不漏。精密的倒车雷达，让你倒车后顾无忧。 舒适典雅的内部空间，不单给您一个优雅的乘车环境，人机工程学的应用、人性化的设计理念，带给您的，将是更多的方便与乐趣。NVH静肃工程，有力的抵抗外部的各种噪音，让车舱内时刻保持静谧。 一匹好马需要耐力，一台好车需要科技。全新福克斯智能、人性化的卓越配备，将带给您全方位顶级享受，彰显同级中的豪华。亿万组防盗密码，每一次启闭都自动更换，时刻为车辆保障强有力的防盗措施。无钥匙进入系统，当您靠近车身1.5米时，门锁便自动打开，进入驾驶舱，踩下刹车，按上POWER启动按钮，引擎立刻启动，豪气尊贵。而此时，启动的，将不仅仅是一台车，更多的，是激情与澎湃！多功能真皮方向盘，让你行车中轻松驾驭、目不离路，进而提高行车安全性。My ford人机交互界面，Ford Eco Mode 模式，时刻为你提供最及时的行车信息，让你轻松掌握、保持车辆的最佳状态。搭载TVC弯道扭力智能分配系统，让你从容应对每一个弯道。人性化设计的：电子助力转向、定速巡航、坡道起步辅助、这些都大大的降低我们的驾车疲劳，让驾驶变的从容。ESC电子车身稳定系统全系标配，同级中绝无仅有，它是时代的先锋，也是当代汽车主动安全的最高代言词！独有的ACS 低速行车安全系统，当时速低于30公里的时候，系统自动开启，有效的防范低速行车中追
比喻句的特点和应用 学习要点 1．了解比喻句的特点，认识比喻句。 2．能够按要求写简单的比喻句。 学习点窍 1．我们在课文中经常能读到这样的句子：“正桥笔直的公路上，一对对玉兰花灯柱，像等候检阅的队伍，站得整整齐齐。”“翠鸟蹬开苇秆，像箭一样飞过去。”“还没看见瀑布，先听见瀑布的声音，好像叠叠的浪涌上岸滩，又像阵阵的风吹过松林。”这几个句子都是比喻句。运用比喻句可以更好地表达思想感情，使语言准确、鲜明、生动，具有更大的说服力和感染力。 比喻，就是打比方。也就是说用浅显的、大家比较熟悉的事物来比喻抽象的、深奥的、人们比较陌生的事物。它是利用两种不同种类的事物之间的某点相似来进行说明或者描写。 一般说来一个比喻句包括三个部分：本体、喻体和比喻词。通常把被比的事物叫作“本体”，把拿来作比的事物叫作“喻体”，把用来联系“本体”和“喻体”的词语叫作“比喻词”。 比喻有三种类型：明喻、暗喻、借喻。三年级主要运用的是明喻，明喻就是明显的打比方，句子的格式是“甲像乙”，在表达时，本体、喻体、比喻词都出现。明喻常用的比喻词是：“像”、“好像”、“像……似的”、“仿佛”、“如同”等等。如：“孔雀那美丽的尾巴抖动着，像一把五彩洒金的大扇子。”本体：孔雀那抖动着的美丽的尾巴，喻体：五彩洒金的大扇子，比喻词：像。 2．比喻句和非比喻句的区别。 在阅读中，我们常常碰到一些句子，句中虽然也有“像”、“好像”等词语，但不是比喻句，这些非比喻句成了迷惑我们判断真正“比喻句”的敌人。
要牢记不能将比喻词语作为判断比喻句的主要依据，主要应分析句子中是否存在比喻关系。如：“他画的荷花就像刚从湖里摘来的一样。”“画的荷花”和“从湖里摘来的荷花”之间只是简单的像，不是比喻。又如：“猫头鹰的耳朵很特别，好像一对立起来的猫耳朵。”“猫头鹰的耳朵”和“猫耳朵”之间是事实上的相像，不是比喻。而“树叶在空中飞舞，像蝴蝶一样。”用“树叶”(本体)和“蝴蝶”(喻体)两种本质不同的事物，在“空中飞舞”的样子很相似来作比，它们之间用“像”(比喻词)来连接，此句是比喻句。 通过比较，我们应该更清楚地明确比喻句具备以下两个特点：(1)句中有本体、喻体、比喻词三个部分。(2)句中本体、喻体必须是两种不同种类的事物，而且有相似之处，存在着比喻关系。 典型例题 1．仿照例句，标出下列比喻句中的本体、喻体和比喻词。 例：弯弯的月亮好像一条小船。 (本体) (比喻词) (喻体) (1)美丽的彩虹像一座弯弯的长桥。 ( ) ( ) ( ) (2)黄澄澄的柿子像一盏盏小灯笼挂满了枝头。 ( ) ( ) ( ) 解析比喻的特点是用两个不同种类的而有相似之处的事物作比。(1)句中有本体、比喻词，应补充上喻体：“绿色的海洋”。把小兴安岭连绵起伏的山上一望无际的树木连成片的样子比作“绿色的海洋”。(2)句中有比喻词、喻体，应补充上本体：“翠鸟头上的羽毛”，把翠鸟头上羽毛的样子、颜色比作橄榄色的头巾。
对于中国的大部分人来说车就像房一样是一个奢侈品，每个人都对自己的爱车十分爱惜，甚至就像是自己爱人一样深深的爱上它，不像在美国那样白菜价一样的汽车，丢在路边都没人要。很多人买了车对它是爱护有加，下雨不开郊区不开堵车不开，其实我觉得这样也不好，毕竟实话说得好“爱她就要给她自由嘛！”。不过还有一句话也说得好“爱她，就要了解她的全部”。每个车其实都有它的“内涵”，细细品味才能给你惊喜，真正的做到人车合一。 我有个朋友是九福的销售顾问，对于福克斯这款车他了解的十分的透彻，我去他们店里面看车的时候他就经常给我讲了一些福克斯使用的小窍门，和一些很冷门的功能，这些东西都鲜为人知，再加上我在网上收集的一些小知识。相信大家看了之后遇到很多问题也能自己解决了。 1.车内后视镜防眩目模式 车内后视镜下有一个手拇指盖大小的扳扣，向车后方向一捹，便进入防眩目模式。请注意，以前防炫目就是让你看不到后面。而我们的小福在扳过之后，仍然可以看到后面，而且于扳过之前的视象完全一样！ 2.显示屏延时10分钟 小福锁车后显示屏延时10分钟自动关闭。 3.“伴我回家”功能 夜晚停车熄火后拉一下变光杆(向着方向盘纵向拉抬一下即可)，车灯被点亮，此时你可继续操作锁车程序，锁车后车灯会继续照亮你回家的路，(车灯会自动延时熄灭的)。 3.发动机停止开音响，1小时自动关闭 发动机停止状态下打开音响，是1小时自动关闭。 4.误按摇控开锁没开门，再次自动上锁 误按摇控开锁后，如果没有去做实际开门操作，车门会再次自动上锁。遥控钥匙可以设成一键开锁（原设），也可以设成一键只开驾驶座门、两键全开。福克斯门锁有双重锁闭开启功能。也就是说可以按一下开锁键4门全开，也可以按一下开驾驶座，连续按两下4门全开。个人认为后一种比较安全，特别是在单独一人开门上车的时候，尤其是单身女性。 设置方法：同时按住开锁键和锁车键，看到车灯闪烁2下即设置成功，再同时按可以反复切换两种开启方式。 5.当有一车门没关好，按锁车键时，车灯不闪！ 6. 如果有人恶意阻拦你关车窗，在连续防夹两次后电脑会自动设置为不防夹。如果要恢复，需把玻璃升到离上框一公分处，迅速放一下，再升到顶，不放按键，保持三秒以上，电脑就会变为默认程序。 7.变速保护功能 运行过程中，手动变速箱有防止再变排入1档和倒档功能，停车挂入倒档需要等待片刻 8.中国版发动机 功率有所降低，主要是为适应国内广泛使用的93#汽油；另外，为防止雨季过深的积水损坏发动机，中国版机器的进气口位置也比欧版的要高。 9.后备箱使用 福克斯的后备厢采取的是触点式开关，只需要在开关的位置轻轻按下触点，就可以打开后备厢盖，这给车主在使用方面带来了方便。但福克斯的后备厢在没有锁中控锁的情况下可以任意开启。不止是停车的时候，就是在行驶的时候，只要不锁中控锁，从外部也可以打开后备厢，只有提醒车主们：当心你的后备厢！多锁两次中控锁。 10.音响音量自动调节功能 怠速时音响声音较小；随车速提高，音响声音逐渐增大；行驶中踩下刹车踏板，音响声音立即减小，松开刹车踏板，声音逐渐增大；随车速降低，声音也将逐渐减小。 调出音量自动调节功能的步骤：打开CD，播放状态中，按CD控制面板上的MENU键数下，直至显示"AVC CURVE"，"AVC CURVE"后面的数字0为关闭音量自动调节功能，大于0为开启此功能，数字越大自动调节越明显。 11.小福的CD和收音的高低音是可以分开设置并自动记忆的，以前BASS打到5时听CD刚好，但听FM时低音就显重了，就想当然的认为肯定不能分开调，没想到一试，是可以的，即在CD时调成5，在FM时调成4，就会自己记忆并根据当前处在CD还是FM状态自动回复。 12.自动上锁的功能
新福+新手必备技——利用参照点精准判断车身位置（申精求认证） 本人2013年元月底拿到驾照，2月底提车，新福1.6MT三厢阳光棕。 半年多的驾车经历，勉强算得上丰富。买车之前，除了在驾校开过普桑之外，没有开过任何的四个轮子的车，所以新福提回来之后最紧要的就是在最短时间内熟悉车况，适应各种路况。那段时间里，刻意地找各种不同的路况去练车，各种各样的坡道、盘山路、高速、国道、省道、县道、乡道、村道，虽然路上没有留下痕迹，但我和小福都已走过。 7月圆满完成了我的第一次长途自驾游，陕西-甘肃-青海-内蒙古-宁夏，总里程340 0公里，全程满载，5个成年人，期间没有发生任何不安全事故，平安到家。 好像有点儿啰嗦了，那就进入正题吧。 在驾车的经历中，经常会遇到一些特殊的情况，必须对车身位置有一个准确的判断，否则可能对车辆造成损失或者引发事故。我们当地就有这样一个特殊路况，很有代表性。在一个大桥的两端都设有限宽设施，限宽2.1米。大家看到水泥墩被刮蹭的痕迹了吧，毁车无数呀，经常看到小汽车伴着让揪心的刮蹭声经过大多数都是新车因为大多数新车都是新手开的。 想要避免爱车刮蹭，必须精确控制车身的位置。终于在酝酿了很久之后，专门找了一个星期六的早上，早早的去把车洗得干干净净，拿上相机去好好地做篇作业，和新福车友们交流一下驾车经验。当然，也有网友不赞成用车上的参照点来判断车身位置的，说应该凭感觉，要人车合一呀什么的。我想说的是，人车合一是驾车熟练程度很高时才可以达到的，对于广大的新手来说是不现实的，需要很长的过程才能达到，然而特殊的路况我们可能随时会遇到，必须用非常实用、短时间能掌握的技能去应对，至于人车合一的境界，相信时间长了大家都可以的。
八大常见修辞手法： ①我说你猜：听老师读句子，准确猜出运用了什么修辞手法。 1.叶子出水很高，像亭亭的舞女的裙。（比喻） 2.青的草，绿的叶，各色鲜艳的花，都像赶集似的聚拢来，形成了光彩夺目的春天。（拟人） 3.横眉冷对千夫指 俯首甘为孺子牛。（对偶） 4.爱心是一片照射在冬日的阳光，使贫病交迫的人感到人间的温暖；爱心是一泓出现在沙漠里的泉水，使濒临绝境的人重新看到生活的希望；爱心是一首飘荡在夜空的歌谣，使孤苦无依的人获得心灵的慰藉。（排比） 5.飞流直下三千尺，疑是银河落九天。（夸张） 6.圆规一面愤愤的回转身，一面絮絮的说，慢慢向外走去。（借代） 7.难道我们不应该好好学习吗？（反问） 8.他是这个学校的学生吗？是的，他是。（设问） ②我讲你忆：伴随老师所讲的每种修辞手法的特征，调动以前学习的记忆，巩固所学。
修辞手法一：比喻 教学目标： 1、了解比喻的特点及运用比喻的方法 2、学习运用比喻构造句子 教学设计： 通过比喻句和非比喻句的比较，认识运用比喻句的表达效果：生动，形象。引导学生讨论了解比喻的特点及其运用比喻的方法，通过练习，学习运用比喻句。 教学内容： 1.引入比喻句 2.比喻句的定义、作用、组成 比喻句定义：就是打比方，用浅显、具体、生动的事物来代表抽象、难理解的 事物。 比喻句的作用：比喻说理浅显易懂、使人易于接受；比喻状物能使概括的东西 形象化，给人深刻的印象。 比喻句的组成：一般有本体、喻体、比喻词。通常把被比的事物叫作“本体”， 把拿来作比的事物叫作“喻体”，把用来联系“本体”和“喻体”的词语叫 作“比喻词”。 “比喻词”有：好像、像、如同、好似等 （认识比喻句，分析比喻句的组成，分辨比喻句 例如：“孔雀那美丽的尾巴抖动着，像一把五彩洒金的大扇子。” 本体：尾巴；喻体：大扇子；比喻词：像。
常用修辞手法的特点及其作用 1、比喻:比喻就是“打比方”。即抓住两种不同性质的事物的相似点,用一事物来喻另一事物。比喻的结构一般由本体(被比喻的事物、喻体(作比方的事物和比喻词(比喻关系的标志构成。构成比喻的关键:甲和乙必须是本质不同的事物,甲乙之间必须有相似点,否则比喻不能成立。 作用:比喻的作用主要是:化平淡为生动;化深奥为浅显;化抽象为具体;化冗长为简洁。用在记叙、说明、描写中,能使事物生动、形象、具体,给人以鲜明的印象;用在议论文中,能使抽象道理变得具体,使深奥的道理变得浅显易懂。最常用的还是生动形象。 如:窄窄的木板,是一支飞鸣的利箭。 小小的三角帆,是一支彩色的大翅膀 2、借代:借代不直接说出所要表述的人或事物,而用与其相关的事物来代替。它强调两事物间的相关点 作用:能起到突出形象,使之具体、生动的效果。 如:你们是初升的太阳,希望寄托在你们身上。 3、夸张:夸张指为追求某种表达效果,对原有事物进行合乎情理的着意扩大或缩小。要求使用时不能失去生活的基础和根据,不能浮夸。 作用:烘托气氛,增强联想,给人启示。可以引起丰富的想象,更好地突出事物的特征,引起读者的强烈共鸣。如:白发三千丈,缘愁似个长。 4、对偶:对偶就是“对对子”,也称“对仗”。它必须是一对字数相等,词性相对,结构相同,意义相关的短语或句子。两句间的关系有承接、递进、因果、假设和条件等。
作用:形式上音节整齐匀称、节奏感强,具有音律美;内容上凝练集中,概括力强。如:四十年别井离乡,雁沓鱼沉;五百个月缺月圆,梦萦魂牵。 5、排比:排比由三个或三个以上结构相同或相似,内容相关、语气一致的短语或句子组合而成。常用强调的同一词语重复出现在各个短语或句子的同一位置上。 作用:可增强语言的气势,强调内容,加重感情。用来说理,可把道理阐述得更严密、更透彻;用来抒情,可把感情抒发得淋漓尽致。(增强气势,说服力强,感染力强。 如:人生旅途中有多少携手相伴的朋友,多少次肝胆相照,多少次投桃报李,又有多少美丽温暖的回忆漫漫长路,总有朝夕相处的亲人,多少叮咛,多少呵护,多少孝心,多少无私。 6、设问:无疑而问”。往往明知故问,自问自答或提出问题不需要确定答案。 作用:引起读者思考。用在标题上,能吸引读者,启发读者思考,更好地体现文章的中心;用在一段的开头或结尾处,除引起思考外,还有承上启下的过渡作用;用在议论文中,能使论证深入,脉络清晰。(设问能强调问题,引起人们注意,启发人们思考。 如:白色的花含有什么色素呢?白色的花什么色素也没有。 7、反问:反问的特点也是“无疑而问”,用疑问句的形式表示确定的意思,句末一般打问号,有的也打感叹号。 作用:以加强语气,增强表达效果,起强调作用。(反问能强调语气,发人深思,激发读者感情,增强肯定(否定语气。 如:历史上没有一个反人民的势力不被人民毁灭的!希特勒、墨索里尼,不都在人民面前倒下去了吗? 8、拟人:使事物人格化,使语言富有神采比拟:把物当作人来写(拟人,把人当作物来写(拟物。作用:印象鲜明,便于表达作者感情。
（1）是对事物的特征进行描绘或渲染，使事物生动具体，给人留下鲜明深刻的印象； （2）是用浅显的或人们熟悉的事物对深奥难懂的的事物加以说明，便于人们深入理解。 拟人主要的作用有： （1）生动形象的写出了事物的特点，把事物写活了，使文章更生动，事物特点更突出 （2）形象地写出事物特征，并且可以使文章耐看，不枯燥无味使描写的事物具有了人的感情，使文章更具有情趣容易理解 反问主要的作用有： （1）可以加强语气，发人深思，激发读者感情，加深读者印象，增强文中的气势和说服力，为文章奠定一种激昂的感情基调。 设问主要的作用有： （1）引起别人注意，启发读者思考，也可以加强作者想表达的思想，引出下文,承上启下。 （2）强烈地表达了句子的主要内容. 排比主要的作用有： （1）给人以一气呵成之感，节奏感强，增强语言气势，加强表达效果。
（1）深刻、生动地揭示事物的本质。 （2）烘托气氛，增强语言的感染力和表达的效果。 （3）给人以深刻的印象，引起读者丰富的想象和强烈共鸣
修辞手法的作用： (1)比喻的作用是能将表达的内容说得生动、具体、形象。给人以深刻鲜明的形象，使说理更透彻。 (2)拟人的作用是使具体事物人格化，语言生动、形象。 (3)夸张的其作用是揭示事物的本质，烘托气氛，引起联想，使表达的事物更突出、更鲜明。 (4)排比的作用是增强语言气势，深化思想内容，增强文章的说服力和感染力。 (5)对偶的主要作用是整齐匀称，节奏感强，高度概括，有音乐美。 (6)对比的作用是能使语言色彩鲜明，事物的性质、特征等更加鲜明突出。 (7)反复的作用是突出思想，强调感情，有时能够加强节奏感。 (8)借代的作用是可引人联想，形象突出、生动、具体、使特点更鲜明。 (9)设问的作用是提醒人们注意、引起思考、突出某些内容。
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