a r X i v :h e p -p h /0202192v 1 20 F e
b 2002
Prospects for the measurement of B 0
s
oscillations with the ATLAS detector at LHC
B.Epp,V.M.Ghete,A.Nairz
Institute for Experimental Physics,University of Innsbruck,Austria
January 31,2002
Abstract.The capabilities of the ATLAS detector to measure the B 0
s oscillations in proton-proton in-teractions at the Large Hadron Collider were evaluated.B 0s candidates in the D ?s π+and D ?s a +1decay modes from semileptonic exclusive events were fully simulated and reconstructed,using a detailed detector description.The sensitivity and the expected accuracy for the measurement of the oscillation frequency were derived from unbinned maximum likelihood amplitude ?ts as functions of the integrated luminosity.A detailed treatment of the systematic uncertainties was performed.The dependence of the measurement sensitivity on various parameters was also evaluated.
1Introduction
The observed B 0s and ˉB 0s
states are linear combinations of two mass eigenstates,denoted here as H and L .Due to the non-conservation of ?avour in charged weak-current
interactions,transitions between B 0s and ˉB 0s
states occur with a frequency proportional to ?m s =m H ?m L .
Experimentally,these B 0s –ˉB 0s oscillations have not yet
been observed directly.In the Standard Model,their fre-quency is predicted in Ref.[1]to be between 12.0ps ?1and 17.6ps ?1with 68%CL,and lower than 20ps ?1at 95%CL,signi?cantly larger than the corresponding value
?m d in the B 0d –ˉB 0d
system.From measurements done by the ALEPH,DELPHI and OPAL experiments at LEP,by SLD at SLC,and by CDF at the Tevatron,a combined lower bound of ?m s >18.0ps ?1has been established
at 95%CL [2].In the B 0d –ˉB 0d
system,the oscillations have been directly observed and a rather precise value of ?m d =0.472±0.017ps ?1[3]has been measured.The values for ?m d and ?m s predicted in the Stan-dard Model by computing the corresponding box diagrams,with the top-quark contribution assumed to be dominant,are proportional to |V td |2and |V ts |2respectively.The di-rect determination of V td and V ts from ?m d and ?m s is,however,hampered by hadronic uncertainties.These uncertainties partially cancel in the ratio:
?m s M B 0d ?B B 0s f 2B 0
s
V td
2,
where M B are the B -meson masses,?B
B are the bag pa-rameters,and f B are the B -meson form https://www.doczj.com/doc/a415845024.html,ing the experimentally-measured masses and a value for the ratio ξ=
?B B 0d f B 0d
which can be computed in lat-tice QCD,a better constraint for V ts /V td can be obtained,
which can then be converted into a constraint of |V td |,the
worst-measured side of the unitarity triangle.
In this note,an evaluation of the capability of the AT-LAS detector to measure the B 0
s oscillations in proton-proton interactions at the Large Hadron Collider (LHC)is presented.Some quantities involved in the measure-ment are still uncertain (cross sections,shape of the back-ground,the ?nal characteristics of the detector),therefore the dependence of the measurement sensitivity and of the expected accuracy on these parameters is also evaluated.
2Event selection
The signal channels considered in this analysis for the
measurement of B 0s –ˉB 0s oscillations are B 0s
→D s πand B 0
s →D s a 1,with D s →φπfollowed by φ→K +K ?.The event samples were generated using PYTHIA 5.7[4],passed then through the ATLAS full GEANT-based simulation program DICE (Inner Detector (ID)only)and reconstructed using an algorithm based on the Kalman ?l-ter implemented in the xKalman package from the ATLAS reconstruction program ATRECON.The physics model used for simulation,the description of the detector and of the reconstruction program are presented in detail in Ref.[5].
In the simulation,b -quark pairs were produced in pp -collisions at
√1
The coordinate system has the z direction along the beam axis,with x -axis pointing to the centre of the accelerator ring and y -axis pointing upwards.The transverse momenta are com-puted with respect to the z axis.
2 B.Epp,V.M.Ghete,A.Nairz:Prospects for the measurement of B0s oscillations with the ATLAS detector at LHC and pseudo-rapidity|η|<2.4which is used by the level-1
trigger to select the B hadronic channels in ATLAS.The
associatedˉb was forced to produce the required B-decay
channels.All the charged?nal-state particles from the B
decay were required to have p T>0.5GeV and|η|<2.5.
The reconstruction of the B0s vertex proceeded via the
following steps(charge-conjugate states are implicitly in-
cluded).Theφdecay vertex was?rst reconstructed by
considering all combinations of pairs of oppositely-charged
tracks with p T>1.5GeV for both tracks.Kinematic cuts
on the angles between the two tracks??KK<10?and
?θKK<10?were also imposed.Here?denotes the az-
imuthal angle andθthe polar angle in the coordinate sys-
tem de?ned previously.The two-track vertex was then?t-
ted assigning the kaon mass to both https://www.doczj.com/doc/a415845024.html,binations
passing a?t-probability[6]cut of1%with the invariant
mass within3σφof the nominalφmass were selected asφ
candidates.To all acceptedφcandidates,a third negative
track with p T>1.5GeV from the remaining ones was
added.The pion mass was assigned to the third track and
a three-track vertex was re?https://www.doczj.com/doc/a415845024.html,binations of three
tracks which had a?t probability greater than1%and an
invariant mass within3σD
s of the nominal D s mass were
selected as D?s candidates.
For each reconstructed D?s meson,a search was made for a+1candidates in three-particle combinations of the re-maining charged tracks.In a?rst step,ρ0mesons were reconstructed from all combinations of two tracks with opposite charges and with p T>0.5GeV for both tracks, each particle in the combination being assumed to be a pion.Kinematic cuts?θππ<15?and??ππ<35?were used to reduce the combinatorial background.The two selected tracks were then?tted as originating from the same vertex;from the combinations passing a?t prob-ability cut of1%,those with an invariant mass within 1.5ΓBW of the nominalρ0mass were selected asρ0can-didates.Next,a positive track with p T>0.5GeV from the remaining charged tracks was added to theρ0can-didate,assuming the pion hypothesis for the extra track. The three tracks were then?tted as originating from a common vertex,without any mass https://www.doczj.com/doc/a415845024.html,bina-tions with a?t probability greater than1%and with an invariant mass within300MeV of the nominal a1mass were selected as a+1candidates.
For the B0s→D?sπ+channel,the B0s decay vertex was reconstructed by considering all D?s candidates and adding a fourth track from the remaining tracks in the event.This track was required to have opposite charge with respect to the pion track from the D?s and p T> 1GeV.The four-track decay vertex was re?tted includ-ingφand D?s mass constraints,and requiring that the total momentum of the B0s vertex pointed to the primary vertex(within the primary vertex spatial resolutions of σx=σy=28μm andσz=46μm)and the momentum of D?s vertex pointed to the B0s vertex.
For the B0s→D?s a+1channel,the B0s candidates were reconstructed combining the D?s candidates with the a+1 candidates.A six-track vertex?t was then performed with mass constraints for the tracks fromφand D s;due to the large a1natural width,the three tracks from the a+1were not constrained to a1mass.As in the B0s→D?sπ+chan-nel,the total momentum of the B0s vertex was required to point to the primary vertex and the momentum of D?s vertex was required to point to the B0s vertex.
In order to be selected as B0s candidates,the four-track and six-track combinations were required to give a probability greater than1%for the vertex?t.The signed separation between the reconstructed B0s vertex and the primary vertex,and between the D?s and B0s vertex were required to be positive(the momentum should not point backward to the parent vertex).To improve the purity of the sample,further cuts were imposed:the accepted B0s candidates were required to have a proper decay time greater than0.4ps,an impact parameter smaller than 55μm and p T>10GeV.
Background to the channels being considered for the measurement of?m s can come from two sources:from other four-or six-body B-hadron decay channels,and from combinatorial background(random combinations with some or all particles not originating from a B decay). For B0s→D?sπ+,the following four-body decay chan-nels were considered as potential sources of background:ˉB0
d→D?sπ+,B0d→D?π+(with D?,D?s→φπ?and φ→K+K?)andΛ0b→Λ+cπ?followed byΛ+c→pK?π+. The similar six-body decay channels considered as poten-tial sources of background for B0s→D?s a+1were:ˉB0d→D?s a+1,B0d→D?a+1(with D?,D?s→φπ?andφ→K+K?)andΛ0b→Λ+cπ?followed byΛ+c→pK?π+π+π?. The simulated four-and six-body background events were passed through the detailed detector-simulation program, reconstructed and analysed using the same programs,the same conditions and the same cuts as the signal events.
In order to study the combinatorial background,a very large sample of simulated inclusive-muon events is needed. The results presented here are based on a sample of1.1 million bˉb→μX events,with p T>6GeV and|η|<2.4 for the muon corresponding to the trigger conditions.
The bˉb→μX sample was analysed in the framework of a fast-simulation program ATLFAST++[5],applying the same algorithms and the same cuts that were used for the fully-simulated samples.A careful check was made of the performance of the fast-simulation program by running it on signal and background samples,and comparing the re-sults with those from the detailed simulation.Reasonable agreement was obtained for the number of reconstructed events and the widths of the mass peaks for the recon-structed particles.
A multi-level trigger is used to select the events for this analysis.The level-1trigger is the inclusive muon trigger mentioned before.The level-2trigger[7]recon?rms the muon from level-1trigger,then in an un-guided search for tracks in the Inner Detector reconstructs aφmeson and,adding a new track,a D s meson.The level-2trigger uses dedicated online software.63%of the signal events selected o?ine pass the level-2trigger cuts;from the bˉb→μX sample,(3.4±0.2)%of the events are selected.The level-3trigger(the event?lter)uses a set of loose o?ine
B.Epp,V.M.Ghete,A.Nairz:Prospects for the measurement of B 0
s oscillations with the ATLAS detector at LHC
3
0100
200
5
5.2
5.4
5.6
E n t r i e s / 10 M e V
M ΚΚππ [GeV ]
Fig. 1.Reconstructed B 0
s invariant-mass distribution for B 0s →D ?s π+
decays.The open histogram shows the signal,
the hatched histogram the background from ˉB 0d →D ?s π+de-cays,and the dark histogram the fake reconstructed decays
from the signal sample.The combinatorial background is not shown here.0
100
200
5 5.2
5.4
5.6E n t r i e s / 10 M e V
M ΚΚππππ [GeV ]
Fig. 2.Reconstructed B 0
s invariant-mass distribution for B 0s →D ?s a +
1decays.The open histogram shows the signal,
the hatched histogram the background from ˉB 0d →D ?s a +1de-cays,and the dark histogram the fake reconstructed decays
from the signal sample.The combinatorial background is not shown here.
B 0s →D ?s π+12.81 5.242389320882370ˉB 0d →D ?s π+ 4.52 2.0899********B 0d →D ?π+
8.21 3.74998923Λ0b →Λ+c (pK ?π+)π?
89.44 2.27998912B 0s →D ?s a +112.81 2.08187841512870ˉB 0d →D ?s a +120.98 3.359699190340B 0d →D ?a +1
8.20 1.40994911Λ0b
→Λ+c (pK ?π+π+π?
)π? 1.970.20
1099400Comb.background sum
1.1×106see text 3750
4 B.Epp,V.M.Ghete,A.Nairz:Prospects for the measurement of B0s oscillations with the ATLAS detector at LHC events are reconstructed in a±2σwindow around B0s
nominal mass.Due to the di?erent decay topology,the
Λ0b→Λ+cπ?channel does not give any contribution to
the background.
The statistics available for estimating the combinato-
rial background are very limited,despite the large size(1.1
million events)of theμX sample.Each simulated event
was therefore passed50times through the fast-simulation
program,di?erent random smearing of the track parame-
ters being applied each time.The number of background
events was counted in a2σmass window around the B0s
nominal mass.On average,0.12events per pass were re-
constructed in the mass window,summing the B0s→D?sπ+
and B0s→D?s a+1channels.Normalising to the number
ofμX events expected for an integrated luminosity of
10fb?1,applying correction factors for the reconstruction
and trigger e?ciencies,the combinatorial background was
estimated to be3752events,and the range of variation was
estimated to be between2079and5425events at90%CL.
Correlations between the results from the50passes were
taken into account.
3Proper-time reconstruction and resolution
The proper time of the reconstructed B0s candidates was
computed from the reconstructed transverse decay length,
d xy,and from th
e B0s transverse momentum,p T:
t=d xy M B0
s
σ1√2σ2
1
+
f21
2π
exp ?(t?t0)2
B.Epp,V.M.Ghete,A.Nairz:Prospects for the measurement of B0s oscillations with the ATLAS detector at LHC5αFraction fαWidthσαFraction fαWidthσα
(%)(fs)(%)(fs)
ˉB0
d→D ?
sπ+ˉB0
d→D
?
s a
+
1
Table2.Proper-time resolution function Res(t|t0)parame-trization with the sum of two Gaussian functions.
dence of the proper-time resolution on the proper time σ(t0)=
2 2
2+μ0cos?m j t0
(1)
where?Γj=Γj H?Γj L,Γj=(Γj H+Γj L)/2andμ0=?1. For the unmixed case(an initial B0j meson decays as a B0j meson at time t0),the probability density is given by the above expression withμ0=+1.The small e?ects of CP violation are neglected in the above relation.Unlike?Γd, which can be safely neglected,the width di?erence in the B0s–ˉB0s system?Γs could be as much as20%of the total width[8].
The above probability is modi?ed by experimental ef-fects.The probability as a function ofμ0and the recon-structed proper time t is obtained as the convolution of p j(t0,μ0)with the proper time resolution Res j(t|t0):
q j(t,μ0)=N ∞t min p j(t0,μ0)Res j(t|t0)d t0
with N a normalization factor.Assuming a fractionωj of wrong tags at production or decay,the probability be-comes:
q j(t,μ)=(1?ωj)q j(t,μ)+ωj q j(t,?μ)(2)
For each signal channel,the background is composed of oscillating B0d mesons with probability given by the ex-pression(2)and of combinatorial background,with prob-ability given by the reconstructed proper time distribu-tion.For a fraction f k j of the j component(j=s,d,and
100
200
300
-0.4-0.200.2
0.4
E
n
t
r
i
e
s
/
.
2
p
s
t-t
[ps]
Fig.5.Proper-time resolution for the decay chan-
nel B0s→D?sπ+.The curve displays the resolution
as obtained from the Res(t|t0)function given in the
text.
25
50
75
100
125
-0.4-0.200.2
0.4
E
n
t
r
i
e
s
/
.
2
p
s
t-t
[ps]
Fig.6.Proper-time resolution for the decay chan-
nel B0s→D?s a+1.The curve displays the resolution
as obtained from the Res(t|t0)function given in the
text.
combinatorial background cb)in the total sample of type k,one obtains the probability density:
pdf k(t,μ)= j=s,d,cb f k j[(1?ωj)q j(t,μ)+ωj q j(t,?μ)]
The index k=1denotes the B0s→D?sπ+channel and k=2the B0s→D?s a+1channel.The likelihood of the
6 B.Epp,V.M.Ghete,A.Nairz:Prospects for the measurement of B0s oscillations with the ATLAS detector at LHC total sample is written as
L(?m s,?Γs)=N ch
k=1N k ev i=1pdf k(t i,μi)(3)
where N k ev is the total number of events of type k,and N ch=2.Each pdf k was properly normalized to unity.
5Extraction of?m s measurement limits and accuracy
The maximum value of?m s measurable in ATLAS was estimated using a simpli?ed Monte Carlo model.The in-put parameters of this model were:for each signal chan-nel k the number of signal events,N k sig,the number of
background events from B0d decays,N k
B0
d ,and th
e num-
ber of events for the combinatorial background,N k cb;the characteristics of the events involved in the computation of the proper-time resolution(see below);the wrong-tag fraction.The wrong-tag fraction was assumed to be the same for both B0s and B0d mesons:ωs=ωd=0.22(see Ref.[9]).A Monte Carlo sample with N sig=N1sig+N2sig signal events oscillating with a given frequency?m s to-
gether with N B0
d =N1
B0
d
+N2
B0
d
background events oscil-
lating with frequency?m d and N cb=N1cb+N2cb combi-natorial events(no oscillations),was generated in the fol-lowing way.For each event with an oscillating b hadron, the true proper time was generated according to an expo-nential distribution with the slope[?Γ(1±?Γ/(2Γ))]?1 which takes into account the contribution of a non-zero ?Γ.HereΓ=Γs,?Γ=?Γs for B0s events andΓ=Γd,?Γ=0for B0d events.The sign in the slope is chosen according to the contribution of each proper time,corre-sponding toΓ(1±?Γ/(2Γ)),to the exponential decay from Eq.(1),e?Γj t0cosh(?Γj t0/2),where the cosh term was factorized from the expression in parentheses and in-cluded in the exponential part.The uncertainty on the
measurement of the transverse decay length,σd
xy ,and the
true value of the g-factor,g0,were generated at random according to the distributions obtained from the simulated samples,?tted with appropriate combinations of Gaussian and exponential functions.From the computed true decay length,d0xy=t0/g0,the corresponding reconstructed de-
cay length was generated as d xy=d0xy+S d
xy σd
xy
?.The
reconstructed g-factor was generated as g=g0+g0S g?′. Both?and?′are random numbers distributed accord-ing to the normal distribution.From the transverse de-cay length and g-factor,the reconstructed proper time was then computed as t=gd xy.The probability for the event to be mixed or unmixed was determined from the t0 and?m s values(?m d value if the event was a B0d event) using the expression(1?cos(?m j t0)/cosh(?Γj t0/2))/2 left out from Eq.(1)after the exponential part is ex-tracted.For a fraction of the events,selected at random, the state was changed between mixed and unmixed,ac-cording to the wrong-tag fraction,ωtag.For the combi-natorial background,the reconstructed proper time was generated assuming that it has the same distribution as the one for B0s mesons.Half of the combinatorial events
were added to the mixed events and half to the unmixed
events.
5.1?m s measurement limits
The?m s measurement limits were obtained applying the amplitude?t method[10]to the‘data sample’generated
as above.In this method a new parameter,the B0s oscilla-
tion amplitude A,is introduced in the likelihood function by replacing the term‘μ0cos?m s t0’with‘μ0A cos?m s t0’in the B0s probability density function given by Eq.(1).
For each value of?m s,the new likelihood function is
minimized with respect to A,keeping all other param-
eters?xed,and a value A±σstat
A
is obtained.One ex-pects,within the estimated uncertainty,A=1for?m s close to its true value,and A=0for?m s far from the true value.One de?nes a5σmeasurement limit as the value of?m s for which1/σA=5,and a sensitivity at95%con?dence limit as the value of?m s for which 1/σA=1.645.Limits are computed with the statistical
uncertaintyσstat
A
,and,in some cases,with the total un-
certaintyσtotal
A
=σstat
A
+σsyst
A
.The systematic uncertainty
σsyst
A
is described in the next section.
5.2Systematic uncertainties
The systematic uncertainties on the B0s oscillation ampli-
tudeσsyst
A
are computed as
σsyst
A
=?A+(1?A)
?σstat
A
B.Epp,V.M.Ghete,A.Nairz:Prospects for the measurement of B 0
s oscillations with the ATLAS detector at LHC
7
A
0.0450?0.11460.1892?0.03370.04200.0072?0.29060.4318?0.5406σstat
A ±0.0476
±0.0707
±0.0895
±0.1183
±0.1673
±0.2456
±0.3570
±0.5640
±0.9300
σsyst A
+0.0967?0.0838
+0.1285?0.1018
+0.1297?0.0960
+0.1468?0.1144
+0.1796?0.1424
+0.2035?0.1580
+0.2980?0.2264
+0.3674?0.2658
+0.3636?0.2592
Table 3.The oscillation amplitude A and its statistical and systematic uncertainties as a function of ?m s for an integrated luminosity of 10fb ?1.The contribution of each component to the systematic uncertainty is also given.
uncertainty for an integrated luminosity of 10fb ?1.In the generated event samples,the value of ?m s was set to ?m gen s
=∞.From Table 3,it can be seen that the dominant con-tributions to the systematic uncertainty come from the
uncertainty on f B 0s
fraction and from the parametrization of the proper time resolution.
The uncertainty on f B 0s
fraction has the value given in Ref.[11].It is,however,expected that the uncertainty will be much smaller at the time this analysis will be done with data.Even now (October 2001),the most up-to-date
preliminary value [12]of f B 0s
is 0.099±0.011,the uncer-tainty being at the level of 11%,to be compared with the value of 17%used here for the consistency of the data.If one considers the intense activity in B ?physics,one can assume that an uncertainty of ～5%will be achieved at the time of data analysis.
The uncertainties on the parameters from the param-etrization of the proper time resolution depend on the MC statistics.A larger MC sample can be generated than the one used in this work,in order to reduce these un-certainties.It is therefore reasonable to assume that the uncertainty on the widths from Table 2can be reduced to half of the actual values.
The systematic uncertainties computed with these ‘pro-jected’uncertainties are given in Table 4.For the other contributions,the values from Table 3were used.
The value of the systematic uncertainty as computed here should be considered with caution,as a rough esti-mate.5.3Results
The amplitude as a function of ?m s for the nominal set of parameters de?ned in the previous sections,?Γs =0and an integrated luminosity of 10fb ?1is shown in Fig.7.
Fig.8shows the signi?cance of the measurement in units of σA .The 5σmeasurement limit is 22.5ps ?1and the 95%CL sensitivity is 36.0ps ?1,when computed with the statistical uncertainty https://www.doczj.com/doc/a415845024.html,puted with the total un-certainty,the 5σmeasurement limit is 16.0ps ?1and the 95%CL sensitivity is 34.5ps ?1for the actual systematic uncertainties,and 21ps ?1and 35.5ps ?1for the projected systematic uncertainties.
For an integrated luminosity of 30fb ?1,the 5σmea-surement limit is 29.5ps ?1and the 95%CL sensitivity is 41.0ps ?1,computed with the statistical uncertainty only.The 5σmeasurement limit and the 95%CL sensitiv-ity become 18.5ps ?1and 37.5ps ?1,respectively,for the actual set of systematic uncertainties and 27.0ps ?1and 40.5ps ?1for the projected systematic uncertainties.
6Dependence of ?m s measurement limits on experimental quantities
Some quantities involved in the measurement of the B 0
s oscillations are not yet known with enough precision.The cross section for b ˉb production could be more than twice the assumed cross section [5];some decay branching ra-tios are also not well determined.The value of ?Γs is not yet measured.The characteristics of the detector could be slightly di?erent,depending on the ?nal con?guration of the detector.The shape and the fraction of the back-ground will depend,among other factors,on the accelera-tor luminosity and on the characteristics of the detector.It is therefore necessary to estimate the dependence of the measurement sensitivity for various values of the param-eters.The limits presented in this section are computed with the statistical error only.
The dependence of the ?m s measurement limits on ?Γs /Γs was determined for an integrated luminosity of 30fb ?1,other parameters having the nominal value.The
8
B.Epp,V.M.Ghete,A.Nairz:Prospects for the measurement of B 0
s oscillations with the ATLAS detector at LHC
A
0.0450?0.11460.1892?0.03370.04200.0072?0.29060.4318?0.5406σstat
A ±0.0476
±0.0707
±0.0895
±0.1183
±0.1673
±0.2456
±0.3570
±0.5640
±0.9300
σsyst A
+0.0494?0.0492
+0.0564?0.0471
+0.0596?0.0475
+0.0679?0.0617
+0.0848?0.0661
+0.0976?0.0823
+0.1370?0.1167
+0.1660?0.1411
+0.1747?0.1496
Table 4.The oscillation amplitude A and its statistical and systematic uncertainties as a function of ?m s for an integrated luminosity of 10fb ?1,computed with the ‘projected uncertainties’on proper time parametrization and on f s .See the text for details.
-5
5
10
A m p l i t u d e
?m s [ps -1
]
Fig.7.The B 0
s oscillation amplitude as a function of ?m s for an integrated luminosity of 10fb ?1.
24
6
8
10
S i g n i f i c a n c e (σ)
?m s [ps -1]
Fig.8.The measurement signi?cance as a function of ?m s for an integrated luminosity of 10fb ?1.
20
40
60
020*********
?m s l i m i t s [p s -1]
?Γs /Γs [%]
Fig.9.The dependence of ?m s measurement limits on ?Γs /Γs .
?Γs /Γs was used as a ?xed parameter in the amplitude ?t method.The results are shown in Fig.9and the numerical values are given in Table 5.No sizeable e?ect is seen up to ?Γs /Γs <30%,therefore ?Γs was set to zero for all other cases.
029.541.01029.541.02029.541.03029.041.04029.040.58027.039.0100
25.538.0
B.Epp,V.M.Ghete,A.Nairz:Prospects for the measurement of B 0
s oscillations with the ATLAS detector at LHC
9
020
40
60
0.3
0.5
1.
2.
3.
5.
?m s l i m i t s [p s -1]
∫ Ldt [10 fb -1
]
Fig.10.The dependence of ?m s measurement limits on the integrated luminosity.
The dependence of the ?m s measurement limits on the integrated luminosity is shown in Fig.10,with the numerical values given in Table 6.
517.532.01022.536.02027.039.03029.541.0
τcbg 5σlimit 95%CL sensitivity
(ps)(ps ?1)(ps ?1)
Table 7.The dependence of ?m s measurement limits on the decay time of the combinatorial background,assuming an ex-ponential decay.
20
40
60
00.51 1.52
?m s l i m i t s [p s -1]
N cbg /N cbg
(nom)
Fig.12.The dependence of ?m s measurement limits on the number of events for the combinatorial background.
10 B.Epp,V.M.Ghete,A.Nairz:Prospects for the measurement of B0s oscillations with the ATLAS detector at LHC
0.5031.042.5
0.7530.541.5
1.0029.541.0 1.2529.040.5 1.5028.540.0Luminosity?m gen
s?m
rec
s±σ
?m s
stat
±σ?m s
syst
Obs.
(fb?1)(ps?1)(ps?1)
15.015.021±0.049±0.002
10
22.522.396±0.072±0.0055σlimit
15.014.942±0.028±0.004
3020.020.010±0.043±0.002
29.529.708±0.083±0.0075σlimit
B.Epp,V.M.Ghete,A.Nairz:Prospects for the measurement of B0s oscillations with the ATLAS detector at LHC11
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“的、地、得”的用法和区别 导入（进入美妙的世界啦~） “的、地、得”口诀儿歌 的地得，不一样，用法分别记心上， 左边白，右边勺，名词跟在后面跑。 美丽的花儿绽笑脸，青青的草儿弯下腰， 清清的河水向东流，蓝蓝的天上白云飘， 暖暖的风儿轻轻吹，绿绿的树叶把头摇， 小小的鱼儿水中游，红红的太阳当空照， 左边土，右边也，地字站在动词前， 认真地做操不马虎，专心地上课不大意， 大声地朗读不害羞，从容地走路不着急， 痛快地玩耍来放松，用心地思考解难题， 勤奋地学习要积极，辛勤地劳动花力气， 左边两人双人得，形容词前要用得， 兔子兔子跑得快，乌龟乌龟爬得慢， 青青竹子长得快，参天大树长得慢， 清晨锻炼起得早，加班加点睡得晚， 欢乐时光过得快，考试题目出得难。 知识典例（注意咯，下面可是黄金部分！） 的、地、得 “的”、“地”、“得”的用法区别本是中小学语文教学中最基本的常识，但在使用中也最容易发生混淆，再加上一段时间里，中学课本中曾将这三个词的用法统一为“的”，因此造成了很多人对它们的用法含混不清进而乱用一通的现象。
一、“的、地、得”的基本概念 1、“的、地、得”的相同之处。 “的、地、得”是现代汉语中高频度使用的三个结构助词，都起着连接作用；它们在普通话中都读轻声“de”，没有语音上的区别。 2、“的、地、得”的不同之处。 吕叔湘、朱德熙所著《语法修辞讲话》认为“的”兼职过多，负担过重，而力主“的、地、得”严格分工。50 年代以来的诸多现代汉语论著和教材，一般也持这一主张。从书面语中的使用情况看，“的”与“地”、“得”的分工日趋明确，特别是在逻辑性很强的论述性、说明性语言中，如法律条款、学术论著、外文译著、教科书等，更是将“的”与“地”、“得”分用。 “的、地、得”在普通话里都读轻声“de”，但在书面语中有必要写成三个不同的字：在定语后面写作“的”，在状语后面写作“地”，在补语前写作“得”。这样做的好处，就是可使书面语言精确化。 二、“的、地、得”的用法 1、的——定语的标记，一般用在主语和宾语的前面。“的”前面的词语一般用来修饰、限制“的”后面的事物，说明“的”后面的事物怎么样。结构形式一般为：形容词、名词（代词）+的+名词。如： ①颐和园(名词)的湖光山色（主语）美不胜收。 ②她是一位性格开朗的女子(名词，宾语)。 2、地——状语的标记，一般用在谓语（动词、形容词）前面。“地”前面的词语一般用来形容“地”后面的动作，说明“地”后面的动作怎么样。结构方式一般为：形容词（副词）+地+动词（形容词）。如： ③她愉快(形容词)地接受(动词，谓语)了这件礼物。 ④天渐渐(时间副词)地冷(形容词，谓语)起来。 3、得——补语的标记，一般用在谓语后面。“得”后面的词语一般用来补充说明“得”前面的动作怎么样，结构形式一般为：动词（形容词）+得+副词。如： ⑤他们玩(动词，谓语)得真痛快(补语)。
of与for的用法以及区别 for 表原因、目的 of 表从属关系 介词of的用法 （1）所有关系 this is a picture of a classroom （2）部分关系 a piece of paper a cup of tea a glass of water a bottle of milk what kind of football，American of soccer？ （3）描写关系 a man of thirty 三十岁的人 a man of shanghai 上海人 （4）承受动作 the exploitation of man by man．人对人的剥削。 （5）同位关系 It was a cold spring morning in the city of London in England． （6）关于，对于 What do you think of Chinese food？ 你觉得中国食品怎么样？ 介词 for 的用法小结 1. 表示“当作、作为”。如: I like some bread and milk for breakfast. 我喜欢把面包和牛奶作为早餐。What will we have for supper? 我们晚餐吃什么?
2. 表示理由或原因,意为“因为、由于”。如: Thank you for helping me with my English. 谢谢你帮我学习英语。 Thank you for your last letter. 谢谢你上次的来信。 Thank you for teaching us so well. 感谢你如此尽心地教我们。 3. 表示动作的对象或接受者,意为“给……”、“对…… (而言)”。如: Let me pick it up for you. 让我为你捡起来。 Watching TV too much is bad for your health. 看电视太多有害于你的健康。 4. 表示时间、距离,意为“计、达”。如: I usually do the running for an hour in the morning. 我早晨通常跑步一小时。We will stay there for two days. 我们将在那里逗留两天。 5. 表示去向、目的,意为“向、往、取、买”等。如: let’s go for a walk. 我们出去散步吧。 I came here for my schoolbag.我来这儿取书包。 I paid twenty yuan for the dictionary. 我花了20元买这本词典。 6. 表示所属关系或用途,意为“为、适于……的”。如: It’s time for school. 到上学的时间了。 Here is a letter for you. 这儿有你的一封信。 7. 表示“支持、赞成”。如: Are you for this plan or against it? 你是支持还是反对这个计划? 8. 用于一些固定搭配中。如: Who are you waiting for? 你在等谁? For example, Mr Green is a kind teacher. 比如,格林先生是一位心地善良的老师。
to与for的用法和区别 一般情况下, to后面常接对象; for后面表示原因与目的为多。 Thank you for helping me. Thanks to all of you. to sb.表示对某人有直接影响比如，食物对某人好或者不好就用to; for表示从意义、价值等间接角度来说，例如对某人而言是重要的，就用for. for和to这两个介词，意义丰富，用法复杂。这里仅就它们主要用法进行比较。 1. 表示各种“目的” 1. What do you study English for? 你为什么要学英语？ 2. She went to france for holiday. 她到法国度假去了。 3. These books are written for pupils. 这些书是为学生些的。 4. hope for the best, prepare for the worst. 作最好的打算，作最坏的准备。 2．对于 1．She has a liking for painting. 她爱好绘画。 2．She had a natural gift for teaching. 她对教学有天赋/ 3．表示赞成同情，用for不用to. 1. Are you for the idea or against it? 你是支持还是反对这个想法？ 2. He expresses sympathy for the common people.. 他表现了对普通老百姓的同情。 3. I felt deeply sorry for my friend who was very ill. 4 for表示因为，由于（常有较活译法） 1 Thank you for coming. 谢谢你来。 2. France is famous for its wines. 法国因酒而出名。 5．当事人对某事的主观看法，对于（某人），对…来说（多和形容词连用）用介词to，不用for.. He said that money was not important to him. 他说钱对他并不重要。 To her it was rather unusual. 对她来说这是相当不寻常的。 They are cruel to animals. 他们对动物很残忍。 6．for和fit, good, bad, useful, suitable 等形容词连用，表示适宜，适合。 Some training will make them fit for the job. 经过一段训练，他们会胜任这项工作的。 Exercises are good for health. 锻炼有益于健康。 Smoking and drinking are bad for health. 抽烟喝酒对健康有害。 You are not suited for the kind of work you are doing. 7. for表示不定式逻辑上的主语，可以用在主语、表语、状语、定语中。 1．It would be best for you to write to him. 2．The simple thing is for him to resign at once. 3．There was nowhere else for me to go. 4．He opened a door and stood aside for her to pass.
的、地、得的用法和区别 的、地、得的用法和区别老班教育 一、的、地、得的基本概念 1、的、地、得的相同之处。 的、地、得是现代汉语中高频度使用的三个结构助词，都起着连接作用；它们在普通话中都读轻声de，没有语音上的区别。 2、的、地、得的不同之处。 吕叔湘、朱德熙所著《语法修辞讲话》认为的兼职过多，负担过重，而力主的、地、得严格分工。50 年代以来的诸多现代汉语论著和教材，一般也持这一主张。从书面语中的使用情况看，的与地、得的分工日趋明确，特别是在逻辑性很强的论述性、说明性语言中，如法律条款、学术论著、外文译著、教科书等，更是将的与地、得分用。 的、地、得在普通话里都读轻声de，但在书面语中有必要写成三个不同的字：在定语后面写作的，在状语后面写作地，在补语前写作得。这样做的好处，就是可使书面语言精确化。 二、的、地、得的用法 （一）、用法 1、的——定语的标记，一般用在主语和宾语的前面。的前面的词语一般用来修饰、限制的后面的事物，说明的后面的事物怎么样。 结构形式一般为：形容词、名词（代词）+的+名词。如： 颐和园(名词)的湖光山色（主语）美不胜收。 她是一位性格开朗的女子(名词，宾语)。 2、地——状语的标记，一般用在谓语（动词、形容词）前面。地前面的词语一般用来形容地后面的动作，说明地后面的动作怎么样。 结构方式一般为：形容词（副词）+地+动词（形容词）。如： 她愉快(形容词)地接受(动词，谓语)了这件礼物。 天渐渐(时间副词)地冷(形容词，谓语)起来。 3、得——补语的标记，一般用在谓语后面。得后面的词语一般用来补充说明得前面的动作怎么样。 结构形式一般为：动词（形容词）+得+副词。如： 他们玩(动词，谓语)得真痛快(补语)。 她红(形容词，谓语)得发紫(补语)。 （二）、例说 的，一般用在名词和形容词的后面，用在描述或限制人物、事物时，形容的词语与被形容的词语之间，表示一种描述的结果。如：漂亮的衣服、辽阔的土地、高大的山脉。结构一般为名词（代词或形容词）+的+名词。如，我的书、你的衣服、他的孩子，美丽的景色、动听的歌曲、灿烂的笑容。 地，用法简单些，用在描述或限制一种运动性质、状态时，形容的词语与被形容的词语之间。结构通常是形容词+地+动词。前面的词语一般用来形容后面的动作。一般地的后面只跟动词。比如高兴地跳、兴奋地叫喊、温和地说、飞快地跑；匆匆地离开；慢慢地移动......... 得，用在说明动作的情况或结果的程度时，说明的词语与被说明的词语之间，后面的词语一般用来补充和说明前面的情况。比如。跑得飞快、跳得很高、显得高雅、显得很壮、馋得直流口水、跑得快、飞得高、走得慢、红得很……得通常用在动词和形容词（动词之间）。
For的用法 1. 表示“当作、作为”。如: I like some bread and milk for breakfast. 我喜欢把面包和牛奶作为早餐。 What will we have for supper? 我们晚餐吃什么? 2. 表示理由或原因,意为“因为、由于”。如: Thank you for helping me with my English. 谢谢你帮我学习英语。 3. 表示动作的对象或接受者,意为“给……”、“对…… (而言)”。如: Let me pick it up for you. 让我为你捡起来。 Watching TV too much is bad for your health. 看电视太多有害于你的健康。 4. 表示时间、距离,意为“计、达”。如: I usually do the running for an hour in the morning. 我早晨通常跑步一小时。 We will stay there for two days. 我们将在那里逗留两天。 5. 表示去向、目的,意为“向、往、取、买”等。如: Let’s go for a walk. 我们出去散步吧。 I came here for my schoolbag.我来这儿取书包。 I paid twenty yuan for the dictionary. 我花了20元买这本词典。 6. 表示所属关系或用途,意为“为、适于……的”。如: It’s time for school. 到上学的时间了。 Here is a letter for you. 这儿有你的一封信。 7. 表示“支持、赞成”。如: Are you for this plan or against it? 你是支持还是反对这个计划? 8. 用于一些固定搭配中。如: Who are you waiting for? 你在等谁? For example, Mr Green is a kind teacher. 比如,格林先生是一位心地善良的老师。 尽管for 的用法较多，但记住常用的几个就可以了。 to的用法: 一：表示相对，针对 be strange (common, new, familiar, peculiar) to This injection will make you immune to infection. 二：表示对比，比较 1：以-ior结尾的形容词，后接介词to表示比较，如：superior ,inferior,prior,senior,junior 2: 一些本身就含有比较或比拟意思的形容词，如equal，similar，equivalent，analogous A is similar to B in many ways.
介词for用法归纳 用法1：(表目的)为了。如： They went out for a walk. 他们出去散步了。 What did you do that for? 你干吗这样做？ That’s what we’re here for. 这正是我们来的目的。 What’s she gone for this time? 她这次去干什么去了？ He was waiting for the bus. 他在等公共汽车。 【用法说明】在通常情况下，英语不用for doing sth 来表示目的。如： 他去那儿看他叔叔。 误：He went there for seeing his uncle. 正：He went there to see his uncle. 但是，若一个动名词已名词化，则可与for 连用表目的。如： He went there for swimming. 他去那儿游泳。(swimming 已名词化) 注意：若不是表目的，而是表原因、用途等，则其后可接动名词。(见下面的有关用法) 用法2：(表利益)为，为了。如： What can I do for you? 你想要我什么？ We study hard for our motherland. 我们为祖国努力学习。 Would you please carry this for me? 请你替我提这个东西好吗？ Do more exercise for the good of your health. 为了健康你要多运动。 【用法说明】(1) 有些后接双宾语的动词(如buy, choose, cook, fetch, find, get, order, prepare, sing, spare 等)，当双宾语易位时，通常用for 来引出间接宾语，表示间接宾语为受益者。如： She made her daughter a dress. / She made a dress for her daughter. 她为她女儿做了件连衣裙。 He cooked us some potatoes. / He cooked some potatoes for us. 他为我们煮了些土豆。 注意，类似下面这样的句子必须用for： He bought a new chair for the office. 他为办公室买了张新办公椅。 (2) 注意不要按汉语字面意思，在一些及物动词后误加介词for： 他们决定在电视上为他们的新产品打广告。 误：They decided to advertise for their new product on TV. 正：They decided to advertise their new product on TV. 注：advertise 可用作及物或不及物动词，但含义不同：advertise sth＝为卖出某物而打广告；advertise for sth＝为寻找某物而打广告。如：advertise for a job=登广告求职。由于受汉语“为”的影响，而此处误加了介词for。类似地，汉语中的“为人民服务”，说成英语是serve the people，而不是serve for the people，“为某人的死报仇”，说成英语是avenge sb’s death，而不是avenge for sb’s death，等等。用法3：(表用途)用于，用来。如： Knives are used for cutting things. 小刀是用来切东西的。 This knife is for cutting bread. 这把小刀是用于切面包的。 It’s a machine for slicing bread. 这是切面包的机器。 The doctor gave her some medicine for her cold. 医生给了她一些感冒药。 用法4：为得到，为拿到，为取得。如： He went home for his book. 他回家拿书。 He went to his friend for advice. 他去向朋友请教。 She often asked her parents for money. 她经常向父母要钱。
《“的、地、得”的用法》语文微课教案 一、教学背景 在语言文字规范化大背景下，帮助学生解决应用“的地得”的疑惑与困难。 二、设计思路 针对学生对于“的地得”的误用与忽视展开教学，规范结构助词“的地得”的使用。按照“问题的提出、问题的分析、问题的解决”的思路展开教学，总结归纳优化的方式方法。 三、教学目标 1、知道“怎么样的什么、怎么样地干什么、干得怎么样”三种固定搭配。 2、掌握“的、地、得”的区别与联系。 3、运用小儿歌“动前土、名前白、行动后面双人来”的口诀帮助正确使用“的、地、得”。 四、教学重难点 1、知道“的、地、得”的区别。 2、在实际情境中正确运用“的、地、得”。 五、教学时间 8分钟微课堂 六、教学适用对象 义务教育九年制内的学生 七、教学准备
多媒体课件、录屏软件 八、教学设计与过程 开场白： 同学们好！今天我们一起来学习“的、地、得”的正确用法。首先我们来了解一下它们的区别。 1、相同之处：原来它们都是念轻声“de”，都是结构助词，起连接作用。 2、不同之处：在书面语中要写成三个不同的字，而且它们的搭配及用法也各不相同。 （1）怎么样的什么 （2）怎样样地干什么 （3）干得怎么样 下面我们就来学习一下它们的正确用法。 白勺“的”的结构是用“形容词或名词或代词+的+名词”来表示，而我们最常见，用得最多的还是“形容词+的+名词”的结构。 而土也“地”的用法可以用“形容词+地+动词”的结构来表示。 双人“得”是用“动词+得+形容词”的结构来表示 3、练习巩固 （1）形近区分 静静（的）河面静静（地）写字欢乐（的）山谷
欢乐（地）歌唱满意（地）点头满意（的）作品 （2）类别区分 1）跑（得）飞快飞快（地）跑 2）愉快（的）旅行旅行（得）愉快 3）强烈（的）渴望强烈（地）渴望 （3）综合杂糅 小雏鹰飞到大树的上方，高兴地喊起来：“我真的会飞啦！而且飞（得）很高呢！” 小结：能填对这个句子的你肯定就已经学会它们的用法了！ 4、特殊情况 质疑：假如遇到特殊情况怎么办呢？ 我从书包里拿出书交给她们，她们高兴得．围着我跳起舞来。（出自二年级上册《日记两则》） （1）质疑：为什么这里要使用“得”呢？ （2）释疑：原来这里强调的是心情，动词在后，形容词在前，相当于后置，“得”修饰“跳舞”而非“围”。现在你明白了吧？ 5、小结归纳： 怎么样，你们学会了吗？为了让同学们能够更快的记住它们的用法，老师送给大家一首口诀来帮助你们熟记三个“的”的正确使用方法：动前土、名前白、行动后面双人来。
of 1....的,属于 One of the legs of the table is broken. 桌子的一条腿坏了。 Mr.Brown is a friend of mine. 布朗先生是我的朋友。 2.用...做成的;由...制成 The house is of stone. 这房子是石建的。 3.含有...的;装有...的 4....之中的;...的成员 Of all the students in this class,Tom is the best. 在这个班级中,汤姆是最优秀的。 5.(表示同位) He came to New York at the age of ten. 他在十岁时来到纽约。 6.(表示宾格关系) He gave a lecture on the use of solar energy. 他就太阳能的利用作了一场讲演。 7.(表示主格关系) We waited for the arrival of the next bus. 我们等待下一班汽车的到来。
I have the complete works of Shakespeare. 我有莎士比亚全集。 8.来自...的;出自 He was a graduate of the University of Hawaii. 他是夏威夷大学的毕业生。 9.因为 Her son died of hepatitis. 她儿子因患肝炎而死。 10.在...方面 My aunt is hard of hearing. 我姑妈耳朵有点聋。 11.【美】(时间)在...之前 12.(表示具有某种性质) It is a matter of importance. 这是一件重要的事。 For 1.为,为了 They fought for national independence. 他们为民族独立而战。 This letter is for you. 这是你的信。
1.两者都可以引出间接宾语，但要根据不同的动词分别选用介词to 或for：(1) 在give, pass, hand, lend, send, tell, bring, show, pay, read, return, write, offer, teach, throw 等之后接介词to。 如： 请把那本字典递给我。 正：Please hand me that dictionary. 正：Please hand that dictionary to me. 她去年教我们的音乐。 正：She taught us music last year. 正：She taught music to us last year. (2) 在buy, make, get, order, cook, sing, fetch, play, find, paint, choose,prepare, spare 等之后用介词for 。如： 他为我们唱了首英语歌。 正：He sang us an English song. 正：He sang an English song for us. 请帮我把钥匙找到。 正：Please find me the keys. 正：Please find the keys for me. 能耽搁你几分钟吗(即你能为我抽出几分钟吗)? 正：Can you spare me a few minutes? 正：Can you spare a few minutes for me? 注：有的动词由于搭配和含义的不同，用介词to 或for 都是可能的。如：do sb a favour＝do a favour for sb 帮某人的忙 do sb harm＝do harm to sb 对某人有害
“的、地、得”的用法教案 教学目标： 1.能通过看视频知道“的、地、得”的用法区别。 2.能在小组合作中正确掌握“的、地、得”的用法。 3.能正确熟练地运用“的、地、得”。 教学重点：通过看视频知道“的、地、得”的用法区别。 教学难点：正确熟练地运用“的、地、得”。 教学过程： 一、导入（板书课题：“的、地、得”的用法“的、地、得”） 这三个字认识吧！虽然它们都有一个相同的读音de，但用法却不一样，可不能把他们用错了。究竟他们的用法有什么不同，我们来听听他们的故事吧！ 二、看微视频，学习“的、地、得”的用法区别。 三、小结： 1.孩子们，刚才看了视频知道他们是谁吗？（白勺的，土也地，双人得。） （1）白勺的是个杂货铺老板，她的店里都有什么？（彩色的毛巾美味的汉堡结实的帐篷舒适的儿童车捕捉风的网会唱歌的小树开个没完的花朵优美动听的歌曲飘来飘去的云……）还可能有什么？ 你们一定会发现，白勺的的用法有什么特点？（后面是名词。）板书：名词 （2）土也地是个运动男孩，他喜欢？（悠闲地散步欢快地跳舞兴奋地跳跃开心地捕蝴蝶看图书踢球骑自行洗澡吃冰淇淋……）他还可能喜欢干什么呢？你发现了吗？土也地的用法特点？（后面是动词。）板书：动词 （3）双人得呢？她是个总喜欢评价别人的小妹妹。（球踢得真棒舞跳得精彩长得好高呀……） 她可能还怎么评价别人？（歌唱得动听饭吃得很饱人长得漂亮）你们会发现，双人得的前面通常都是——动词。板书：动词 2.小结：所以，他们的用法也很简单，区别就在这里。 （白勺的用在名词前面；土也地用在动词前面；双人得用在动词后面。）你明白了吗？ 四、我来考考你们，看哪一组完成得又对又快！ 1.菜鸟级练习 2.老鸟级练习 3.大虾级练习 五、总结
for的用法： 1. 表示“当作、作为”。如: I like some bread and milk for breakfast. 我喜欢把面包和牛奶作为早餐。 What will we have for supper? 我们晚餐吃什么? 2. 表示理由或原因,意为“因为、由于”。如: Thank you for helping me with my English. 谢谢你帮我学习英语。 Thank you for your last letter. 谢谢你上次的来信。 Thank you for teaching us so well. 感谢你如此尽心地教我们。 3. 表示动作的对象或接受者,意为“给……”、“对…… (而言)”。如: Let me pick it up for you. 让我为你捡起来。 Watching TV too much is bad for your health. 看电视太多有害于你的健康。 4. 表示时间、距离,意为“计、达”。如:
I usually do the running for an hour in the morning. 我早晨通常跑步一小时。 We will stay there for two days. 我们将在那里逗留两天。 5. 表示去向、目的,意为“向、往、取、买”等。如: Let’s go for a walk. 我们出去散步吧。 I came here for my schoolbag.我来这儿取书包。 I paid twenty yuan for the dictionary. 我花了20元买这本词典。 6. 表示所属关系或用途,意为“为、适于……的”。如: It’s time for school. 到上学的时间了。 Here is a letter for you. 这儿有你的一封信。 7. 表示“支持、赞成”。如: Are you for this plan or against it? 你是支持还是反对这个计划? 8. 用于一些固定搭配中。如:
1.表示各种“目的”，用for （1）What do you study English for 你为什么要学英语？ （2）went to france for holiday. 她到法国度假去了。 （3）These books are written for pupils. 这些书是为学生些的。 （4）hope for the best, prepare for the worst. 作最好的打算，作最坏的准备。 2．“对于”用for （1）She has a liking for painting. 她爱好绘画。 （2）She had a natural gift for teaching. 她对教学有天赋/ 3．表示“赞成、同情”，用for （1）Are you for the idea or against it 你是支持还是反对这个想法？ （2）He expresses sympathy for the common people.. 他表现了对普通老百姓的同情。 （3）I felt deeply sorry for my friend who was very ill. 4. 表示“因为，由于”（常有较活译法），用for （1）Thank you for coming. 谢谢你来。
（2）France is famous for its wines. 法国因酒而出名。 5．当事人对某事的主观看法，“对于（某人），对…来说”，（多和形容词连用），用介词to，不用for. （1）He said that money was not important to him. 他说钱对他并不重要。 （2）To her it was rather unusual. 对她来说这是相当不寻常的。 （3）They are cruel to animals. 他们对动物很残忍。 6．和fit, good, bad, useful, suitable 等形容词连用，表示“适宜，适合”，用for。（1）Some training will make them fit for the job. 经过一段训练，他们会胜任这项工作的。 （2）Exercises are good for health. 锻炼有益于健康。 （3）Smoking and drinking are bad for health. 抽烟喝酒对健康有害。 （4）You are not suited for the kind of work you are doing. 7. 表示不定式逻辑上的主语，可以用在主语、表语、状语、定语中。 （1）It would be best for you to write to him. （2） The simple thing is for him to resign at once.
加入收藏夹 主题： 介词试题It’s + 形容词 + of sb. to do sth.和It’s + 形容词 + for sb. to do sth.的用法区别。 内容： It's very nice___pictures for me. A.of you to draw B.for you to draw C.for you drawing C.of you drawing 提交人：杨天若时间：1/23/2008 20:5:54 主题：for 与of 的辨别 内容：It's very nice___pictures for me. A.of you to draw B.for you to draw C.for you drawing C.of you drawing 答：选A 解析：该题考查的句型It’s + 形容词+ of sb. to do sth.和It’s +形容词+ for sb. to do sth.的用法区别。 “It’s + 形容词+ to do sth.”中常用of或for引出不定式的行为者，究竟用of sb.还是用for sb.，取决于前面的形容词。 1) 若形容词是描述不定式行为者的性格、品质的，如kind，good，nice，right，wrong，clever，careless，polite，foolish等，用of sb. 例： It’s very kind of you to help me. 你能帮我，真好。 It’s clever of you to work out the maths problem. 你真聪明，解出了这道数学题。 2) 若形容词仅仅是描述事物，不是对不定式行为者的品格进行评价，用for sb.，这类形容词有difficult，easy，hard，important，dangerous，（im）possible等。例： It’s very dangerous for children to cross the busy street. 对孩子们来说，穿过繁忙的街道很危险。 It’s difficult for u s to finish the work. 对我们来说，完成这项工作很困难。 for 与of 的辨别方法： 用介词后面的代词作主语，用介词前边的形容词作表语，造个句子。如果道理上通顺用of，不通则用for. 如： You are nice.(通顺，所以应用of)。 He is hard.(人是困难的，不通，因此应用for.) 由此可知，该题的正确答案应该为A项。 提交人：f7_liyf 时间：1/24/2008 11:18:42
1. 两者都可以引出间接宾语，但要根据不同的动词分别选用介词to 或for： (1) 在give, pass, hand, lend, send, tell, bring, show, pay, read, return, write, offer, teach, throw 等之后接介词to。 如： 请把那本字典递给我。 正：Please hand me that dictionary. 正：Please hand that dictionary to me. 她去年教我们的音乐。 正：She taught us music last year. 正：She taught music to us last year. (2) 在buy, make, get, order, cook, sing, fetch, play, find, paint, choose,prepare, spare 等之后用介词for 。如： 他为我们唱了首英语歌。 正：He sang us an English song. 正：He sang an English song for us. 请帮我把钥匙找到。 正：Please find me the keys. 正：Please find the keys for me. 能耽搁你几分钟吗(即你能为我抽出几分钟吗)? 正：Can you spare me a few minutes? 正：Can you spare a few minutes for me? 注：有的动词由于搭配和含义的不同，用介词to 或for 都是可能的。如： do sb a favou r do a favour for sb 帮某人的忙 do sb harnn= do harm to sb 对某人有害
的、得、地的用法：动词前提土旁、动词后双人旁、一动不动白字旁 （一） 的地得，不一样，用法分别记心上， 左边白，右边勺，名词跟在后面跑。 美丽的花儿绽笑脸，青青的草儿弯下腰， 清清的河水向东流，蓝蓝的天上白云飘， 暖暖的风儿轻轻吹，绿绿的树叶把头摇， 小小的鱼儿水中游，红红的太阳当空照， 左边土，右边也，地字站在动词前， 认真地做操不马虎，专心地上课不大意， 大声地朗读不害羞，从容地走路不着急， 痛快地玩耍来放松，用心地思考解难题， 勤奋地学习要积极，辛勤地劳动花力气， 左边两人就使得，形容词前要用得， 兔子兔子跑得快，乌龟乌龟爬得慢， 青青竹子长得快，参天大树长得慢， 清晨锻炼起得早，加班加点睡得晚， 欢乐时光过得快，考试题目出得难。 （二）“的、地、得”快板 的地得、的地得，用作助词都读de. 作文写话用不准，朗读往往会念错。 有趣的活动、绿的树，活动是事，树是物。 事物前面用的字，小朋友们都记着。 认真地想、快快地跑，想跑看摸是动作。 动作前面用地字，位置千万不要挪。 看得清，记得准，唱得好，飞得高。 动作后面用得字，补充说明要记牢。 （三）“的、地、得”用法简要口诀 名词前面“白勺”“的”， 动词前面“土也”“地”， 形容动后“双人”“得”， 当作助词都读“de”。 二、“的、地、得”用法小析 “的”后面跟的都是表示事物名称的词或词语，如：敬爱的总理、慈祥的老人、戴帽子的男孩、珍贵的教科书、鸟的天堂、伟大的祖国、有趣的情节、优雅的环境、可疑的情况、团结友爱的集体、他的妈妈、可爱的花儿、谁的橡皮、清清的河水...... “地”后面跟的都是表示动作的词或词语，如：高声地喊、愉快地唱、拼命地逃、疯狂地咒骂、严密地注视、一次又一次地握手、迅速地包围、沙沙地直响、斩钉截铁地说、从容不迫地申述、用力地踢、仔细地看、开心地笑笑......” “得”前面跟的多数是表示动作的词或词语，后面跟的都是形容事物状态的词或词语，表示怎么怎么样的，如：走得很快、踩得稀烂、疼得直叫唤、瘦得皮包骨头、红得发紫、气得双脚直跳、理解得十分深刻、乐得合不拢嘴、惊讶得目瞪口呆、大得很、扫得真干净、笑得多甜啊...... 三、“的、地、得”的用法补充说明：
to和for的用法有什么不同（一） 一、引出间接宾语时的区别 两者都可以引出间接宾语，但要根据不同的动词分别选用介词to 或for，具体应注意以下三种情况： 1. 在give, pass, hand, lend, send, tell, bring, show, pay, read, return, write, offer, teach, throw 等之后接介词to。如： 请把那本字典递给我。 正：Please hand me that dictionary. 正：Please hand that dictionary to me. 她去年教我们的音乐。 正：She taught us music last year. 正：She taught music to us last year. 2. 在buy, make, get, order, cook, sing, fetch, play, find, paint, choose, prepare, spare 等之后用介词for 。如： 他为我们唱了首英语歌。 正：He sang us an English song. 正：He sang an English song for us. 请帮我把钥匙找到。 正：Please find me the keys. 正：Please find the keys for me. 能耽搁你几分钟吗(即你能为我抽出几分钟吗)? 正：Can you spare me a few minutes?
正：Can you spare a few minutes for me? 3. 有的动词由于用法和含义不同，用介词to 或for 都是可能的。如： do sb a favor＝do a favor for sb 帮某人的忙 do sb harm＝do harm to sb 对某人有害 在有的情况下，可能既不用for 也不用to，而用其他的介词。如： play sb a trick＝play a trick on sb 作弄某人 请比较： play sb some folk songs＝play some folk songs for sb 给某人演奏民歌 有时同一个动词，由于用法不同，所搭配的介词也可能不同，如leave sbsth 这一结构，若表示一般意义的为某人留下某物，则用介词for 引出间接宾语，即说leave sth for sb；若表示某人死后遗留下某物，则用介词to 引出间接宾语，即说leave sth to sb。如： Would you like to leave him a message? / Would you like to leave a message for him? 你要不要给他留个话？ Her father left her a large fortune. / Her father left a large fortune to her. 她父亲死后给她留下了一大笔财产。 二、表示目标或方向的区别 两者均可表示目标、目的地、方向等，此时也要根据不同动词分别对待。如： 1. 在come, go, walk, move, fly, ride, drive, march, return 等动词之后通常用介词to 表示目标或目的地。如： He has gone to Shanghai. 他到上海去了。 They walked to a river. 他们走到一条河边。