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ORIGINAL ARTICLE
Diffusion tensor imaging in the cervical spinal cord
Ting Song ?Wen-Jun Chen ?Bo Yang ?
Hong-Pu Zhao ?Jian-Wei Huang ?Ming-Jin Cai ?
Tian-Fa Dong ?Tang-Sheng Li
Received:12January 2009/Revised:2August 2010/Accepted:25September 2010/Published online:13October 2010óSpringer-Verlag 2010
Abstract There are discrepancy between MR ?ndings and clinical presentations.The compressed cervical cord in patients of the spondylotic myelopathy may be normal on conventional MRI when it is at the earlier stage or even if patients had severe symptoms.Therefore,it is necessary to take a developed MR technique—diffusion tensor imaging (DTI)—to detect the intramedullary lesions.Prospective MR and DTI were performed in 53patients with cervical compressive myelopathy and twenty healthy volunteers.DTI was performed along six non-collinear directions with single-shot spin echo echo-planar imaging (EPI)sequence.Intramedullary apparent diffusion coef?cient (ADC)and fractional anisotropy (FA)values were measured in four segments (C2/3,C3/4,C4/5,C5/6)for volunteers,in lesions (or the compressed cord)and normal cord for patients.DTI original images were processed to produce color DTI maps.In the volunteers’group,cervical cord exhibited blue on the color DTI map.FA values between four segments had a signi?cant difference (P \0.01),with the highest FA value (0.85±0.03)at C2/3level.However,ADC value between them had no signi?cant difference (P [0.05).For patients,only 24cases showed hyperin-tense on T2-weighted image,while 39cases shown patchy
green signal on color DTI maps.ADC and FA values between lesions or the compressed cord and normal spinal cord of patients had a signi?cant difference (both P \0.01).FA value at C2/3cord is the highest of other segments and it gradually decreases towards the caudal https://www.doczj.com/doc/849076957.html,ing single-shot spin echo EPI sequence and six non-collinear diffusion directions with b value of 400s mm -2,DTI can clearly show the intramedullary microstructure and more lesions than conventional MRI.Keywords MR áDiffusion tensor imaging (DTI)áCervical myelopathy áApparent diffusion coef?cient (ADC)áFractional anisotropy (FA)
Introduction
Cervical spondylosis is a very common degenerative dis-ease of the spine in the elderly [2,9].Conventional MR examination has played an important role in the diagnosis of cervical spondylosis,appearing intervertebral disk her-nia,osteophytosis,and cervical canal stenosis,etc.[12].All these conditions could result in cervical compressive myelopathy [3,13,17,21].Spondylotic compressive myelopathy developed progressively for years because of long-standing segmental compression of the spinal cord [8].Moreover,in some severe cases with obvious clinical symptoms such as extremity numbness and motion dys-function,there were no abnormal signal intensity on con-ventional MR imaging.How to explain the difference between the clinical manifestations and the MR ?ndings became very dif?cult for radiologists and orthopedists due to the primary disadvantage of routine MR imaging is unable to display the microstructures of the lesion at the early stage.The earlier treatment yields to better
T.Song (&)áW.-J.Chen áJ.-W.Huang áM.-J.Cai áT.-F.Dong áT.-S.Li
Department of Radiology,The Third Af?liated Hospital of Guangzhou Medical University,No.63Duobao Road,Guangdong 510150,Guangzhou,China e-mail:china_doctor@https://www.doczj.com/doc/849076957.html,
B.Yang áH.-P.Zhao
Department of Orthopedics,The Third Af?liated Hospital of Guangzhou Medical University,
No.63Duobao Road,Guangdong 510150,Guangzhou,China
Eur Spine J (2011)20:422–428DOI 10.1007/s00586-010-1587-3
effectiveness.Therefore,it is very important to diagnose the lesion at the earlier stage.
Diffusion tensor imaging(DTI),a magnetic resonance technique that is sensitive to the diffusion of water mole-cules,can diagnose the acute cerebral stroke which can not be demonstrated on conventional MR examinations[20]. Although DTI has been used widely in the brain[15,18],it was seldom used in the spinal cord because the quality of the images was degraded by artifacts of susceptibility, pulsation of cerebrospinal?uid(CSF),and heart motion or respiration motion[4,6].Additionally,the signal–noise ratio and resolution of images of DTI in human spinal cord was inferior to that of the brain because of the small size of the spinal cord.The purpose of this study was to elucidate the usage of DTI in analyzing the early?ndings of the compressive cervical spinal cord and in depicting the dif-fusion characteristics of cervical cord in healthy volunteers of Chinese.We optimized the scanning parameters and sequences to study the clinical application value of DTI in the human cervical spinal cord by selecting the patients with spondylotic compressive myelopathy and healthy volunteers.
Materials and methods
Study subjects
Fifty-three consecutive patients with cervical compressive myelopathy were prospectively studied from May2006to June2008.There were28males,25females,and the mean age56years(range47–71years).All patients were diagnosed to be the cervical compressive myelopathy based on the clinical manifestations(neck pain,extremity numbness,walking dif?culty,etc.)and imaging modali-ties?ndings.All patients had the cervical spondylotic myelopathy,with calci?cation or thickening of the liga-mentum?avum in30patients,ossi?cation or thickening of the posterior longitudinal ligament in16patients, cervical disc herniation in50patients,and cervical canal stenosis in42patients.The evaluation of myelopathy was performed according to the Japanese Orthopedic Associ-ation(JOA)score for cervical myelopathy[21].Patients with cerebral palsy,rheumatoid arthritis,or other spinal diseases,and those who needed spinal surgery due to kyphotic deformity or severity instability were excluded from this study.
Twenty healthy volunteers(11males and9females, mean age55years,age range46–67years)without neu-rological de?cits and any clinical symptoms were selected to be control group.The protocol followed ethical rules and was approved by our institutional review board,and all patients were informed and gave their consent before study initiation.Both patients and volunteers in control group were followed up for6months.
MR protocol
All imaging was performed using a1.5T scanner(Gyro-scan NT Intera,Philips Medical Systems,the Netherlands) equipped with actively shielded magnetic?eld gradients of up to23mT/m,a slew rate of150mT/m/ms,and a multi-channel all-spine coil.For conventional sequences,scan-ning orientations were sagittal T1-weighted image,sagittal T2-weighted image and transverse T2-weighted image. The images were obtained with a?eld of view(FOV)of 250mm for sagittal scanning and230mm for transverse scanning,and an image matrix2569256.The conven-tional MRI sequences were spin-echo T1-weighted image (TR/TE=500ms/15ms)and fast spin-echo T2-weighted image(TR/TE=4,800ms/120ms).Slice thickness was 3mm,and slice gap0.3mm and numbers of acquisition3.
Single-shot fast spin-echo echo-planar imaging(EPI) was used for DTI acquisition.Parameters for current dif-fusion tensor imaging were obtained as followed:using sagittal plane,slice thickness=3mm,slice gap=0mm, acquisition matrix=1289128,FOV=230mm,num-bers of acquisition=4.Diffusion was measured along six non-collinear directions with two b values(0, 400s mm-2).
Data and images postprocessing and analysis
The diffusion tensor images were transferred to worksta-tion using a software written in interactive data language (IDL version 5.6)and were analyzed off-line by two experienced neuroradiologists(W.J.C,T.F.D)who were blinded to patients’clinical data.Disagreements were resolved via discussion until decisions were reached by consensus.The evaluation focused on the DTI and con-ventional MR images analysis,combined with the radio-graphical?ndings.
The ADC and FA values were measured using regions of interest(ROIs,size50pixels)technique in cervical spinal cord at four different level segments,C2/3,C3/4, C4/5,C5/6for healthy volunteers,in lesions(or the com-pressive cord)and normal segments for patients,respec-tively.The intramedullary lesions were de?ned as the hyperintensity on T2-weighted image or the compressive cervical cord.The normal cord segment for patients was de?ned as the segments1.5cm distant from the lesion.DTI original images were automatically processed using IDL software to produce color DTI maps.The anisotropic dif-fusion in the craniocaudal direction was shown in blue.The diffusion in anterioposterior direction and right-left direc-tion was displayed in red and green,respectively.
Statistics analysis
A standard SPSS12.0for windows (SPSS Institute,Chi-cago,IL)software package was adopted for the statistical analysis.Data were expressed with mean ±stand devia-tion "x
?s .Paired t test,v 2test and one-way ANOVA (analysis of variance)analysis was used.P \0.05was considered statistically signi?cant.
Results
DTI manifestations of cervical spinal cord in healthy volunteers
CSF appeared hyperintense on the ADC map and hypointense on FA map (Fig.1).Cervical spinal cord showed intermedi-ated-intense on the ADC map and hyperintense on FA map.Cervical spinal cord showed a very uniform ADC value on ADC map.On the color DTI map (Fig.2),spinal cord showed blue.Four different level segments of cervical spinal cord,C2/3,C3/4,C4/5,C5/6,were analyzed and found that FA value between them had a signi?cant difference using one-way ANOVA,F =159.24,P \0.01,with the highest FA value (0.85±0.03)of spinal cord segment at C2/3level.However,ADC values between four segments had no sig-ni?cant difference (F =2.08,P [0.05).(Table 1).MRI and DTI manifestations of cervical spinal cord in patients
Conventional T 2-weighted images showed high signal intensity within the cervical cord only in 24cases,without
abnormal signal in 26cases (Figs.3,7).1,2The remaining three cases were excluded from the further analysis because of the poor image quality produced by the motion artifacts.On DTI maps,39cases were found abnormal signal within the cervical spinal cord as follows:high signal intensity on ADC maps (Fig.4),low signal intensity on FA maps (Fig.5)and patchy yellow signal on color DTI maps (Figs.6,8)appearing on otherwise normal blue spinal cord.We found color diffusion tensor images can show more lesions than routine MR images (v 2=9.65,P \0.01).Also,ADC and FA values between lesions (or the compressive cord)and the non-compressive spinal cord had signi?cant difference (Table 2,paired t test,for ADC,t =2.88,P \0.01,for FA,t =2.62,P \0.01).
These volunteers and patients underwent follow-up MR and DTI examination within 6months after the ?rst check-up.No abnormal changes were revealed on the imaging appearances and clinical presentations in volunteers.The patients with minor symptoms without obvious evidence of pathologic re?exes or gait disturbance warrant follow-up observation or non-operative treatment.Operative intervention was per-formed in the patients with severe symptoms,including anterior or posterior approach.These patients took the postoperative MR and DTI examination to evaluate the curative effect,such as decompression of cervical canal,decrease of lesion area.
Discussion
MR imaging,owing to its high soft-tissue resolution,has played an important role in the analyzing the spinal
cord’s
Fig.1Sagittal FA map of cervical spinal cord in a healthy volunteer demonstrating the homogeneous signal intensity of cervical spinal
cord
Fig.2Sagittal color diffusion tensor imaging (DTI)map showing that cervical cord is blue (b =400s mm -2),the same volunteer as in the Fig.1
1Figures 3,4,5,6are from the same patients.
2
Figures 7,8are from 57-year-old patient with spondylotic compressive myelopathy.
gross structure and in the diagnosing lesions of spinal cord. However,the conventional MR imaging could not disclose the microstructure of the spinal cord,such as?ber tract of the white matter.With the development of diffusion-weighted imaging,especially the diffusion tensor imaging,
it becomes possible by analyzing the water molecule dif-fusion motion in https://www.doczj.com/doc/849076957.html,pared with conventional MR imaging,DTI is a promising technique which was used gradually in clinical[6].
Unlike free water,water molecule diffusion in human was hindered by cell alignment pattern,cell membranes, and other intracellular and extracellular structures,showing the anisotropy[6].Moseley et al.[15]reported that diffu-sion-weighted MR imaging can clearly show the ischemic lesions in the rat brain as early as the45min after the occlusion of middle cerebral artery.ADC maps were proved to be sensitive for detecting the early structural changes in the cervical compressive cord[1].We utilized the DTI technique to observe the compressed spinal cord in the cervical spondylosis and canal stenosis.The highly ordered arrangement of axons in the white matter of cer-vical spinal cord makes its diffusion highly anisotropic. Water molecules,due to the limitation of the myelin sheath,moved rapidly along the white matter?ber tract but slowly along other directions.Diffusion anisotropy in the white matter of spinal cord was also con?rmed in vivo by animal experiments in many literatures[5,7,10,11].
In human in vivo,DTI of spinal cord began in1999, Clark et al.[5]?rst reported that water diffusion in spinal
Table1Comparisons of ADC and FA values of cervical cord in20 volunteers
Mean ADC value±SD (910-6mm2s-1)Mean FA value±SD
C2/3level715.35±96.760.85±0.03 C3/4level713.27±86.380.81±0.02 C4/5level728.46±95.690.78±0.02 C5/6level734.42±64.590.66±
0.04
Fig.3Sagittal MR T2WI demonstrating C4/5intervertebral disc herniation and thickness of the ligamentum?avum but without abnormal signal intensity in the cervical spinal
cord Fig.4ADC map of the same patient showing no abnormal signal intensity in the cervical spinal
cord
Fig.5FA map of the same patient showing slight hyperintensity in the cervical spinal cord
cord in human is anisotropic.In 2002,Ries reported the cervical spondylosis and found lesions on DTI map but not showed on conventional MRI [16].However,how to select
the regions of interest became a dilemmatic challenge to radiologists as the cord diffusion anisotropy was measured in sagittal plane,although with a better coverage of lesions,probably including both white matter and gray matter.Notwithstanding it may be easy to discriminate the white matter from the gray matter in transverse plane,the less resolution and poor image quality made the cord anisotropy measured inaccurately.In current study,we still used the sagittal orientation to produce the DTI maps combined with the improved parameters,and the good quality image and cord anisotropy measurement can as well be obtained.Routine MR imaging could show the cervical canal stenosis,protrusion of intervertebral disk,thickening of the ligamentum ?avum and the posterior longitudinal ligament,etc.In this study,abnormal signal intensity was shown only for 24patients in T 2-weighted imaging,but 39patients in DTI colored tensor images,on which green or red signals were seen on normal blue spinal cord.Demir et al.[8]reported the MR study of a group of cervical spondylosis in which 17cases showed injuries on MR ADC maps,while only 13cases in routine MR T2-weighted images.On the contrary,there were no abnormal ?ndings on volunteers’DTI maps.For another 26patients without abnormal signal on all sequences of routine MR,however,the ADC and FA values in the segments of the compressive spinal cord differed obviously with the other segments of non-com-pressed spinal cord.There was no pathological con?rma-tion of intramedullary lesions as it is impossible to get the specimens of human spinal cord in vivo.Nevertheless,those areas showed on DTI maps were correlated well with locations proved by clinical
data.
Fig.6The color DTI map of the same patient showing abnormal green signal intensity in the blue background of normal cervical spinal
cord
Fig.7The routine MR T2WI image demonstrating C5/6interverte-bral disc herniation and thickness of the posterior longitudinal ligament but without abnormal signal intensity in the cervical spinal
cord
Fig.8Sagittal color DTI map of the same patient showing intramedullary the pathy green signal at C5/6level
The cause for the increased ADC values in the com-pressed cord is still uncertain.Tsuchiya et al.[19] explained it was possible that the elevated ADC values indicated the cystic necrosis,syrinx and atrophy were caused by myelomalacia.On our opinions,hyperostosis, intervertebral disk herniation and canal stenosis com-pressing the spinal cord could cause decreasing perfusion which might lead to ischemia and anoxemia and cellular membrane injury that could increase cellular membrane penetrability.And long-term compression to spinal cord may cause CSF to?ow turbulently and to penetrate into spinal cord and to form intramedullary microcysts which cannot be displayed on conventional MR examination [8,14].
The decreased FA values were attributed to the restric-ted diffusion of water molecule in the compressed cord. The intramedullary edema resulted in destroyed balance between intra-and extra-cellular spaces and the combina-tion of water molecule and protein could also cause the decreased diffusivity[14].
The anatomical structure and lesion can be displayed clearly on DTI images with single-shot spin-echo EPI sequence which could reduce the motion artifacts,and six-noncollinear directions using b value of400s mm-2.FA value in spinal cord of Chinese is higher at C2/3level than other levels,the lower FA value at C5/6level.This phe-nomenon,as Wheeler-Kingshott et al.[20]described,may be correlated with the ratio of the white matter to the gray matter.More caudally,the gray matter and the brachial plexus nerve root which cause directional changes of?bers gradually increased,resulting in FA value decreased. Colored-DTI maps can demonstrate lesions not seen on routine MR images.
Although clinicians can thoroughly and neurologically check patients even if without abnormal conventional MR manifestations,they seldom accurately localized the lesion and quantitatively analyzed the lesion.Indeed,once the abnormal signal occurred on the DTI,prophylactic treatment may be taken for severe cases to prevent clinical symptoms deteriorated.There are many conser-vative treatments, e.g.,applying the cervical orthosis which is so feasible that patients can sit up and become ambulatory.Surgery is an alternative option for those patients who fail to achieve recovery after conservative treatment.
In conclusion,DTI can display the earlier alterations of the water molecule within the lesions due to its sensitivity to the movement of water molecule and can explain the discrepancy between conventional MRI?ndings and the clinical manifestations.However,resolution and image quality of DTI of spinal cord is also slightly inferior to that of brain.How to improve the image quality is the main problem in our further study.
Acknowledgments The manuscript submitted was supported by the Medical Science Foundation of the Department of Health of Guangdong Province(No.A2006529),the Medical Science Founda-tion of the Bureau of Health of Guangzhou city(No.2005-YB-040), and Doctoral Scienti?c Research Start-up Foundation of Guangzhou Medical College(No.2006GD081).No bene?ts in any form have been or will be received from a commercial party related directly or indirectly to the subject of this manuscript.
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The way 的用法 Ⅰ常见用法： 1)the way+ that 2)the way + in which（最为正式的用法） 3)the way + 省略（最为自然的用法） 举例：I like the way in which he talks. I like the way that he talks. I like the way he talks. Ⅱ习惯用法： 在当代美国英语中，the way用作为副词的对格，“the way+ 从句”实际上相当于一个状语从句来修饰整个句子。 1)The way =as I am talking to you just the way I’d talk to my own child. He did not do it the way his friends did. Most fruits are naturally sweet and we can eat them just the way they are—all we have to do is to clean and peel them. 2）The way= according to the way/ judging from the way The way you answer the question, you are an excellent student. The way most people look at you, you’d think trash man is a monster. 3）The way =how/ how much No one can imagine the way he missed her. 4）The way =because
一、柴油车辆 CO2排放计算 柴油的CO2排放因子是：74100 kg/TJ柴油的净热值是：43 TJ/Gg 故单位质量柴油完全燃烧排放的CO2质量是：74.1*43/1000 = 3.1863 即1kg柴油排放CO2： 3.1863kg 每升柴油（10号）排放CO2： 3.1863kg*0.84=2.6765kg 每升柴油排放注：柴油含碳量：20.2 kg/GJ；氧化率：100%，碳到二氧化碳的转化系数：44/12，故此：柴油的CO2排放因子计算为： 20.2*100%*44/12*1000 = 74100 kg/TJ 二、天然气车辆 CO2排放计算 天然气的主要成分是甲烷，也有少许乙烷、丙烷和丁烷，此外一般还含有硫化氢、二氧化碳、氮和水气，以及微量的惰性气体，由于天然气的成分并不是一个标准量，只能按照全部为甲烷来计算这样在充分燃烧后： CH4+2O2=CO2+2H20 正好生成一立方米的二氧化碳，质量约为1.964千克。 三、计划更新天然气车辆CO2减排量计算 以2013年为例，一年的燃料单耗天然气与柴油车相比，计算天然气车辆CO2减排量： 1、每升天然气充分燃烧后，产生1.964千克CO2，2013年天然气车辆燃料单耗为40.16立方米/百公里，那么每百公里排放CO2为： 1.964*40.16=78.8742千克/百公里 2、每升柴油（10号）排放CO2为2.6765kg，2013年柴油车辆燃
料单耗为31.63升/百公里，那么每百公里排放CO2为： 31.63*2.6765=84.6577千克/百公里 3、2013年天然气与柴油车型相比天然气车辆每百公里CO2减排量为： 84.6577-78.8742=5.7835千克/百公里 4、2013年平均每车每日行驶里程为135.4公里，即1.354百公里，那么每辆车每年CO2减排量为： 5.7835*1.354*365=2858.4千克 2015年1月1日至2017年12月31日，预投入运行400辆天然气车，400辆天然气车3年的CO2减排量为： 2858.4*3*400=3430.09吨
The way的用法及其含义（二） 二、the way在句中的语法作用 the way在句中可以作主语、宾语或表语： 1.作主语 The way you are doing it is completely crazy.你这个干法简直发疯。 The way she puts on that accent really irritates me. 她故意操那种口音的样子实在令我恼火。The way she behaved towards him was utterly ruthless. 她对待他真是无情至极。 Words are important, but the way a person stands, folds his or her arms or moves his or her hands can also give us information about his or her feelings. 言语固然重要,但人的站姿,抱臂的方式和手势也回告诉我们他(她)的情感。 2.作宾语 I hate the way she stared at me.我讨厌她盯我看的样子。 We like the way that her hair hangs down.我们喜欢她的头发笔直地垂下来。 You could tell she was foreign by the way she was dressed. 从她的穿著就可以看出她是外国人。 She could not hide her amusement at the way he was dancing. 她见他跳舞的姿势，忍俊不禁。 3.作表语 This is the way the accident happened.这就是事故如何发生的。 Believe it or not, that's the way it is. 信不信由你, 反正事情就是这样。 That's the way I look at it, too. 我也是这么想。 That was the way minority nationalities were treated in old China. 那就是少数民族在旧中
定冠词the的用法： 定冠词the与指示代词this ,that同源,有“那(这)个”的意思,但较弱,可以和一个名词连用,来表示某个或某些特定的人或东西. (1)特指双方都明白的人或物 Take the medicine.把药吃了. (2)上文提到过的人或事 He bought a house.他买了幢房子. I've been to the house.我去过那幢房子. (3)指世界上独一无二的事物 the sun ,the sky ,the moon, the earth (4)单数名词连用表示一类事物 the dollar 美元 the fox 狐狸 或与形容词或分词连用,表示一类人 the rich 富人 the living 生者 (5)用在序数词和形容词最高级,及形容词等前面 Where do you live?你住在哪? I live on the second floor.我住在二楼. That's the very thing I've been looking for.那正是我要找的东西. (6)与复数名词连用,指整个群体 They are the teachers of this school.(指全体教师) They are teachers of this school.(指部分教师) (7)表示所有,相当于物主代词,用在表示身体部位的名词前 She caught me by the arm.她抓住了我的手臂. (8)用在某些有普通名词构成的国家名称,机关团体,阶级等专有名词前 the People's Republic of China 中华人民共和国 the United States 美国 (9)用在表示乐器的名词前 She plays the piano.她会弹钢琴. (10)用在姓氏的复数名词之前,表示一家人 the Greens 格林一家人(或格林夫妇) (11)用在惯用语中 in the day, in the morning... the day before yesterday, the next morning... in the sky... in the dark... in the end... on the whole, by the way...
二氧化碳（CO2）包含1个碳原子和2个氧原子，分子量为44（C-12、O-16）。二氧化碳在常温常压下是一种无色无味气体，空气中含有约1%二氧化碳。液碳和固碳是生物体（动物植物的组成物质）和矿物燃料（天然气，石油和煤）的主要组成部分。一吨碳在氧气中燃烧后能产生大约3.67吨二氧化碳（C的分子量为12，CO2的分子量为44，44/12=3.67）。 我们在查看减排二氧化碳的相关计算资料时，有些提到的是“减排二氧化碳量”（即CO2），有些提到的是“碳排放减少量”（以碳计，即C），因此，减排CO2与减排C，其结果是相差很大的。因此要分清楚作者对减排量的具体含义，它们之间是可以转换的，即减排1吨碳（液碳或固碳）就相当于减排3.67吨二氧化碳。 火力发电占我国总发电量约83%，消耗的煤炭约占煤炭消耗总量的49%，因此，以燃烧煤炭的火力发电为参考，计算节电的减排效益。根据专家统计：每节约 1度（千瓦时）电，就相应节约了0.4千克标准煤，同时减少污染排放0.272千克碳粉尘、0.997千克二氧化碳（CO2）、0.03千克二氧化硫（SO2）、0.015千克氮氧化物（NOX）。 为此可以推算出以下公式计算： 节约1度电=减排0.997千克“二氧化碳”=减排0.272千克“碳” 节约1千克标准煤=减排2.493千克“二氧化碳”=减排0.68千克“碳” 节约1千克原煤=减排1.781千克“二氧化碳”=减排0.486千克“碳”（说明：以上电的折标煤按等价值，即系数为1度电=0.4千克标准煤，而1千克原煤=0.7143千克标准煤） 根据相关资料报道，CO2（二氧化碳）的碳（C）排放系数（t/tce）（吨/吨标煤）中，国家发改委能源研究所推荐值为0.67、日本能源经济研究所参考值为0.68、美国能源部能源信息署参考值为0.69，与以上的推算值（0.68）基本相当。应该说，该系数与火电厂的发电煤耗息息相关，发电煤耗降低、排放系数自然也有所降低。 根据BP中国碳排放计算器提供的资料： 节约1升汽油=减排2.3千克“二氧化碳”=减排0.627千克“碳” 节约1升柴油=减排2.63千克“二氧化碳”=减排0.717千克“碳” 物质密度不同重量也不同，1升水重1公斤，原油1升=0.86公斤(1吨=1.17千升=7.35桶)；汽油1升=0.73公斤；煤油1升=0.82公斤；轻柴油1升=0.86公斤；重柴油1升=0.92公斤；1升蒸馏酒=0.912公斤。为此推算： 节约1千克汽油=减排3.15千克“二氧化碳”=减排0.86千克“碳” 节约1千克柴油=减排3.06千克“二氧化碳”=减排0.83千克“碳”
“tｈｅwａｙ+从句”结构的意义及用法 首先让我们来看下面这个句子: Ｒead the foｌloｗｉnｇpassagｅａnd talkａbout ｉt wi ｔh your classmaｔes．Try tｏｔeｌl whaｔyｏu thiｎk ｏf Tom aｎd ｏｆｔhe ｗay the chiｌｄrenｔrｅated ｈim. 在这个句子中，ｔhe waｙ是先行词,后面是省略了关系副词that或in whｉch的定语从句。 下面我们将叙述“the ｗaｙ+从句”结构的用法。 1.tｈe wａy之后，引导定语从句的关系词是tｈat而不是hoｗ,因此，<<现代英语惯用法词典＞＞中所给出的下面两个句子是错误的：Ｔhｉs is ｔｈeｗayｈowｉtｈａppened. This is the way how he ａlwａｙs treats me. 2．在正式语体中,thaｔ可被in which所代替;在非正式语体中，ｔhat则往往省略。由此我们得到theｗay后接定语从句时的三种模式：1) tｈe ｗaｙ＋ｔhａt-从句２）the way +ｉn whiｃh－从句3) the ｗay +从句 例如：Ｔｈe way(in whiｃh ，thａt) ｔhｅｓｅｃomｒade ｓloｏｋａｔｐrobｌems is wrong．这些同志看问题的方法
不对。 Ｔｈｅｗａy(that ,ｉn ｗhiｃh)yoｕ’ｒe doinｇit is comple ｔeｌy crａzy.你这么个干法,简直发疯。 Wｅａdmiｒｅd him for thｅｗay ｉｎｗhｉch he fａｃeｓdiｆficultieｓ． Waｌlａｃe ａｎd Ｄarwiｎｇreed ｏn the way ｉｎwhi ｃh ｄｉfｆｅrｅnt forms ｏf life had ｂegｕn.华莱士和达尔文对不同类型的生物是如何起源的持相同的观点。 Thｉs is ｔｈe ｗaｙ（tｈａｔ) hｅdｉd it. I lｉkeｄｔhe waｙ(ｔhat) ｓｈeｏｒganized ｔhe ｍeetｉng． 3.theｗay(tｈat)有时可以与hｏw(作“如何”解）通用。例如： That’s tｈe ｗaｙ(tｈaｔ) shｅspoke. = Tｈat’s how shｅspoke.
表示“方式”、“方法”，注意以下用法： 1.表示用某种方法或按某种方式，通常用介词in(此介词有时可省略)。如： Do it (in) your own way. 按你自己的方法做吧。 Please do not talk (in) that way. 请不要那样说。 2.表示做某事的方式或方法，其后可接不定式或of doing sth。 如： It’s the best way of studying [to study] English. 这是学习英语的最好方法。 There are different ways to do [of doing] it. 做这事有不同的办法。 3.其后通常可直接跟一个定语从句(不用任何引导词)，也可跟由that 或in which 引导的定语从句，但是其后的从句不能由how 来引导。如： 我不喜欢他说话的态度。 正：I don’t like the way he spoke. 正：I don’t like the way that he spoke. 正：I don’t like the way in which he spoke. 误：I don’t like the way how he spoke. 4.注意以下各句the way 的用法： That’s the way (=how) he spoke. 那就是他说话的方式。 Nobody else loves you the way(=as) I do. 没有人像我这样爱你。 The way (=According as) you are studying now, you won’tmake much progress. 根据你现在学习情况来看，你不会有多大的进步。 2007年陕西省高考英语中有这样一道单项填空题： ——I think he is taking an active part insocial work. ——I agree with you_____. A、in a way B、on the way C、by the way D、in the way 此题答案选A。要想弄清为什么选A，而不选其他几项，则要弄清选项中含way的四个短语的不同意义和用法，下面我们就对此作一归纳和小结。 一、in a way的用法 表示：在一定程度上，从某方面说。如： In a way he was right.在某种程度上他是对的。注：in a way也可说成in one way。 二、on the way的用法 1、表示：即将来(去)，就要来(去)。如： Spring is on the way.春天快到了。 I'd better be on my way soon.我最好还是快点儿走。 Radio forecasts said a sixth-grade wind was on the way.无线电预报说将有六级大风。 2、表示：在路上，在行进中。如： He stopped for breakfast on the way.他中途停下吃早点。 We had some good laughs on the way.我们在路上好好笑了一阵子。 3、表示：(婴儿)尚未出生。如： She has two children with another one on the way.她有两个孩子，现在还怀着一个。 She's got five children，and another one is on the way.她已经有5个孩子了，另一个又快生了。 三、by the way的用法
光伏发电节能减排效果的计算方法 根据国家发改委有关火电厂的耗煤发电数据：平均每千瓦时(即每度)供电需煤耗为360g标准煤(理论值)；然而工业锅炉每燃烧一吨标准煤，产生二氧化碳2620Kg及二氧化硫0.06Kg、一氧化碳0.0227 Kg、氮氧化物0.0360Kg、HC 0.0050Kg、烟尘0.0110 Kg等(因此燃煤锅炉排放废气成为大气的主要污染源之一)1.2MW光伏并网电站，年发电量约为180万度，即系统年节能量180万KWh，因此，项目的节能减排量为：（日新科技园为例） 单位面积节能量=180万KWh÷3.09万m2=58.25KWh/ m2 年节煤量约：360×1800000×10-3＝648000(Kg) 标准煤 年减排量约： CO2量：2620×648000×10-3＝1697760(Kg) SO2量：0.0600×648000＝38880(Kg) CO 量：0.0227×648000＝14709.6(Kg) NOx量：0.0360×648000＝23328(Kg) HC量：0.0050×648000＝3240(Kg) 烟尘量：0.0110×648000＝7128(Kg)
[节能减排]：“能”指代“标准煤（热量单位）”；“排”指“二氧化碳(CO2)”排放或“碳(C)排放”。 [标准煤]: 亦称煤当量。能源的种类很多，所含的热量也各不相同，为了便于相互对比和在总量上进行研究，我国把每kg 含热7000大卡（29306千焦）的定为标准煤（ce），也称标煤。标准煤严格意义上是一个热量单位。即1kgce=7000大卡=29306KJ≈29.3M J。
1、二氧化碳和碳有什么不同？ 二氧化碳（CO2）包含1个碳原子和2个氧原子，分子量为44（C-12、O-16）。二氧化碳在常温常压下是一种无色无味气体，空气中含有约1%二氧化碳。液碳和固碳是生物体（动物植物的组成物质）和矿物燃料（天然气，石油和煤）的主要组成部分。一吨碳在氧气中燃烧后能产生大约3.67吨二氧化碳（C的分子量为12，CO2的分子量为44，44/12=3.67）。 2、节约1度电或1公斤煤到底减排了多少“二氧化碳”或“碳”？ 因此，我们以燃烧煤炭的火力发电为参考，计算节电的减排效益。根据专家统计：每节约 1度（千瓦时）电，就相应节约了0.4千克标准煤，同时减少污染排放0.272千克碳粉尘、0.997千克二氧化碳（CO2）、0.03千克二氧化硫（SO2）、0.015千克氮氧化物（NOX）。 为此可以推算出以下公式计算： 节约1度电=减排0.997千克“二氧化碳”=减排0.272千克“碳” 节约1千克标准煤=减排2.493千克“二氧化碳”=减排0.68千克“碳” 节约1千克原煤=减排1.781千克“二氧化碳”=减排0.486千克“碳” （说明：以上电的折标煤按等价值，即系数为1度电=0.4千克标准煤，而1千克原煤=0.7143千克标准煤） 按折标煤系数1.229算： 节约1度电=节约0.1229千克标煤=减排0.3064千克“二氧化碳” 3、节约1升汽油或柴油减排了多少“二氧化碳”或“碳”？ 根据BP中国碳排放计算器提供的资料： 节约1升汽油=减排2.3千克“二氧化碳”=减排0.627千克“碳” 节约1升柴油=减排2.63千克“二氧化碳”=减排0.717千克“碳”
The way的用法及其含义（一） 有这样一个句子：In 1770 the room was completed the way she wanted. 1770年，这间琥珀屋按照她的要求完成了。 the way在句中的语法作用是什么？其意义如何？在阅读时，学生经常会碰到一些含有the way 的句子，如：No one knows the way he invented the machine. He did not do the experiment the way his teacher told him.等等。他们对the way 的用法和含义比较模糊。在这几个句子中，the way之后的部分都是定语从句。第一句的意思是，“没人知道他是怎样发明这台机器的。”the way的意思相当于how；第二句的意思是，“他没有按照老师说的那样做实验。”the way 的意思相当于as。在In 1770 the room was completed the way she wanted.这句话中，the way也是as的含义。随着现代英语的发展，the way的用法已越来越普遍了。下面，我们从the way的语法作用和意义等方面做一考查和分析： 一、the way作先行词，后接定语从句 以下3种表达都是正确的。例如：“我喜欢她笑的样子。” 1. the way+ in which +从句 I like the way in which she smiles. 2. the way+ that +从句 I like the way that she smiles. 3. the way + 从句(省略了in which或that) I like the way she smiles. 又如：“火灾如何发生的，有好几种说法。” 1. There were several theories about the way in which the fire started. 2. There were several theories about the way that the fire started.
如何计算二氧化碳减排量？ 近年来，全球变暖已成为全世界最关心的环保问题，造成全球变暖的主要原因是大量的温室气体产生，而温室气体的主要组成部分就是二氧化碳（CO2），而二氧化碳的大量排放是现代人类的生产生活造成的，归根到底是大量使用各种化石能源（煤炭、石油、天然气）造成的，根据《京都议定书》的规定，各国纷纷制定了减排二氧化碳的计划。 通过节约化石能源和使用可再生能源，是减少二氧化碳排放的两个关键。在节能工作中，经常需要统计分析二氧化碳减排量的问题，现将网络收集的相关统计方法做一个简单整理，仅供参考。 1、二氧化碳和碳有什么不同？ 二氧化碳（CO2）包含1个碳原子和2个氧原子，分子量为44（C-12、O-16）。二氧化碳在常温常压下是一种无色无味气体，空气中含有约1%二氧化碳。液碳和固碳是生物体（动物植物的组成物质）和矿物燃料（天然气，石油和煤）的主要组成部分。一吨碳在氧气中燃烧后能产生大约3.67吨二氧化碳（C的分子量为12，CO2的分子量为44，44/12=3.67）。 我们在查看减排二氧化碳的相关计算资料时，有些提到的是“减排二氧化碳量”（即CO2），有些提到的是“碳排放减少量”（以碳计，即C），因此，减排CO2与减排C，其结果是相差很大的。因此要分清楚作者对减排量的具体含义，它们之间是可以转换的，即减排1吨碳（液碳或固碳）就相当于减排3.67吨二氧化碳。 2、节约1度电或1公斤煤到底减排了多少“二氧化碳”或“碳”？ 发电厂按使用能源划分有几种类型：一是火力发电厂，利用燃烧燃料（煤、石油及
其制品、天然气等）所得到的热能发电；二是水力发电厂，是将高处的河水通过导流引到下游形成落差推动水轮机旋转带动发电机发电；三是核能发电厂，利用原子反应堆中核燃料慢慢裂变所放出的热能产生蒸汽（代替了火力发电厂中的锅炉）驱动汽轮机再带动发电机旋转发电；四是风力发电场，利用风力吹动建造在塔顶上的大型桨叶旋转带动发电机发电称为风力发电，由数座、十数座甚至数十座风力发电机组成的发电场地称为风力发电场。 以上几种方式的发电厂中，只有火力发电厂是燃烧化石能源的，才会产生二氧化碳，而我国是以火力发电为主的国家（据统计，2006年全国发电总量2.83万亿kWh，其中火电占83.2%，水电占14.7%），同时，火力发电厂所使用的燃料基本上都是煤炭（有小部分的天然气和石油），全国煤炭消费总量的49%用于发电。 因此，我们以燃烧煤炭的火力发电为参考，计算节电的减排效益。根据专家统计：每节约 1度（千瓦时）电，就相应节约了0.4千克标准煤，同时减少污染排放0.272千克碳粉尘、0.997千克二氧化碳（CO2）、0.03千克二氧化硫（SO2）、0.015千克氮氧化物（NOX）。 为此可以推算出以下公式计算： 节约1度电=减排0.997千克“二氧化碳”=减排0.272千克“碳” 节约1千克标准煤=减排2.493千克“二氧化碳”=减排0.68千克“碳” 节约1千克原煤=减排1.781千克“二氧化碳”=减排0.486千克“碳” （说明：以上电的折标煤按等价值，即系数为1度电=0.4千克标准煤，而1千克原煤=0.7143千克标准煤）
way 的用法 【语境展示】 1. Now I’ll show you how to do the experiment in a different way. 下面我来演示如何用一种不同的方法做这个实验。 2. The teacher had a strange way to make his classes lively and interesting. 这位老师有种奇怪的办法让他的课生动有趣。 3. Can you tell me the best way of working out this problem? 你能告诉我算出这道题的最好方法吗？ 4. I don’t know the way (that / in which) he helped her out. 我不知道他用什么方法帮助她摆脱困境的。 5. The way (that / which) he talked about to solve the problem was difficult to understand. 他所谈到的解决这个问题的方法难以理解。 6. I don’t like the way that / which is being widely used for saving water. 我不喜欢这种正在被广泛使用的节水方法。 7. They did not do it the way we do now. 他们以前的做法和我们现在不一样。 【归纳总结】 ●way作“方法，方式”讲时，如表示“以……方式”，前面常加介词in。如例1； ●way作“方法，方式”讲时，其后可接不定式to do sth.，也可接of doing sth. 作定语，表示做某事的方法。如例2，例3；
碳减排数量的简单计算方法 由于碳减排的具体计算方法比较复杂，涉及到具体的项目和方法学。为统一集团内部计算方法，暂按以下方法计算CO2 减排量。如有新的计算方法，再另行通知更改。 具体方法： 一、同等热值的天然气和替代燃料的换算： 1.计算1万方天然气的热值： 10000方* 35588千焦/方= 355880000 千焦 （天然气的热值系数请参考表一）。 2.计算同等热值情况下的替代燃料，以下以原煤为例： 355880000千焦/（20934千焦/公斤）=17000 公斤 （即1万方天然气燃烧热值约等于17000 公斤的原煤燃烧时的热值，原煤的热值系数请参考表一。注：没考虑燃烧效率和其他损耗）。 二、计算天然气和替代燃料的ＣＯ２的排放量： 3.1万方天然气折算成质量单位为： 10000方* （0.76 公斤/方）=7600 公斤 （天然气体积换算成质量单位时统一使用0.76 公斤/方。）4.燃烧1万方天然气的CO2 排放量为： 7600公斤* 0.444kg-C/kg = 3374.4 公斤
（天然气燃烧时ＣＯ２排放量请使用的排放系数表二，统一使用国家环保局温室气体控制项目数据即0.444kg-C/kg）。 5.燃烧17000 公斤的原煤的CO2 排放量为： 17000公斤* 0.748kg-C/kg = 12716.07公斤 （为统一计算，代替燃料只分为煤炭和石油两种，排放系数分别取0.748kg-C/kg和0.５８３kg-C/kg） 三、计算1万方天然气替代其他燃料时的ＣＯ２减排量 6.得到用1万方天然气替换17000 公斤原煤时产生的ＣＯ２减 排量： 12716.07公斤－3374.4 公斤＝9341.67公斤 附录： 表一： 各种能源折算成标准煤的参考系数表： 各种能源折标准煤参考系数
t h e-w a y-的用法
The way 的用法 "the way+从句"结构在英语教科书中出现的频率较高, the way 是先行词, 其后是定语从句.它有三种表达形式:1) the way+that 2)the way+ in which 3)the way + 从句(省略了that或in which),在通常情况下, 用in which 引导的定语从句最为正式,用that的次之,而省略了关系代词that 或 in which 的, 反而显得更自然,最为常用.如下面三句话所示,其意义相同. I like the way in which he talks. I like the way that he talks. I like the way he talks. 一.在当代美国英语中,the way用作为副词的对格,"the way+从句"实际上相当于一个状语从句来修饰全句. the way=as 1)I'm talking to you just the way I'd talk to a boy of my own. 我和你说话就象和自己孩子说话一样. 2)He did not do it the way his friend did. 他没有象他朋友那样去做此事. 3)Most fruits are naturally sweet and we can eat them just the way they are ----all we have to do is clean or peel them . 大部分水果天然甜润,可以直接食用,我们只需要把他们清洗一下或去皮.
减排量计算 主要污染物总量减排计算，主要污染物是指化学需氧量（COD）、二氧化硫（SO2）。 1、化学需氧量的减排计算方法 COD排放量计算（吨）=统计期废水排放量（万吨）×COD排放排放的浓度（mg/l）×0.01 COD减排量计算（吨）=统计期COD排放量（吨）-比较期同期COD 排放量（吨） 小结：从计算公式上可以看出，减排量的大小取决于两方面；（一）废水外排量的大小（二）COD污染因子排放浓度。各个单位应根据本单位实际情况，从这两个方面寻找减排途径，加大对废水治理设施改造，降低COD排放浓度，提高治理后外排水综合利用率，减少废水外排量。 例：某项目采取某项措施，投入试运行时间为六月底(相当于全年运行6个月)，日排放废水量为1万吨/天，治理前COD排放浓度为156 mg/l，治理后COD排放标浓度为80mg/l， COD主要减排量计算过程如下： COD减排量计算（吨）=1×(80-156) ×6×30×0.01=-136.8 2、二氧化硫的减排量计算方法 按照物料衡算法：二氧化硫排放量（吨）=燃煤消费量（吨）×含硫率×0.8×2×（1-脱硫效率）
二氧化硫减排量（吨）=统计期二氧化硫排放量（吨）-比较期同期二氧化硫排放量（吨） 小结：从计算公示上可以看出，二氧化硫减排量大小取决（一）燃煤消耗量（二）提高脱硫效率上两种途径。各个单位根据本单位实际情况，从这两个方面寻找减排途径，改造除尘脱硫治理设施提高脱硫效率，减少燃煤用量从而减少二氧化硫的排放量。 例：某企业有两台十蒸吨锅炉，平时一开一备，上年统计年耗煤量为11000吨，燃料煤平均含硫率为1%，采用水膜除尘的方式进行除尘，未采用脱硫措施，该企业上年统计二氧化硫排放量为176吨；当年该企业对两台十蒸吨锅炉进行改造，新上碱水脱硫设施，脱硫效率为75%，碱水脱硫设施于当年六月一日投入试运行，试算当年该企业二氧化硫的减排量。 物料衡算法 企业于六月一日投入试运行，当年进行脱硫处理的燃料煤（A）为：A=7/12×11000=6416吨 燃料燃烧二氧化硫排放量=燃料煤消费量×含硫率×0.8×2×（1-脱硫效率） 上年二氧化硫排放量=11000×1%×0.8×2×(1-0)=176吨 当年二氧化硫排放量=未经脱硫处理的燃煤产生的二氧化硫排放量+经脱硫设施处理燃煤产生的二氧化硫排放量=（11000-6416）×1%×0.8×2×(1-0)+6416×1%×0.8×2×（1-0.75)=73.34+25.66=99.00当年二氧化硫减排量=176-99.0=77吨
way的用法总结大全 way的用法你知道多少，今天给大家带来way的用法，希望能够帮助到大家，下面就和大家分享，来欣赏一下吧。 way的用法总结大全 way的意思 n. 道路,方法,方向,某方面 adv. 远远地，大大地 way用法 way可以用作名词 way的基本意思是“路,道,街,径”,一般用来指具体的“路,道路”,也可指通向某地的“方向”“路线”或做某事所采用的手段,即“方式,方法”。way还可指“习俗,作风”“距离”“附近,周围”“某方面”等。 way作“方法,方式,手段”解时,前面常加介词in。如果way前有this, that等限定词,介词可省略,但如果放在句首,介词则不可省略。
way作“方式,方法”解时,其后可接of v -ing或to- v 作定语,也可接定语从句,引导从句的关系代词或关系副词常可省略。 way用作名词的用法例句 I am on my way to the grocery store.我正在去杂货店的路上。 We lost the way in the dark.我们在黑夜中迷路了。 He asked me the way to London.他问我去伦敦的路。 way可以用作副词 way用作副词时意思是“远远地,大大地”,通常指在程度或距离上有一定的差距。 way back表示“很久以前”。 way用作副词的用法例句 It seems like Im always way too busy with work.我工作总是太忙了。 His ideas were way ahead of his time.他的思想远远超越了他那个时代。 She finished the race way ahead of the other runners.她第一个跑到终点,远远领先于其他选手。 way用法例句
t h e_w a y的用法大全
The way 在the way+从句中, the way 是先行词, 其后是定语从句.它有三种表达形式:1) the way+that 2)the way+ in which 3)the way + 从句(省略了that或in which),在通常情况下, 用in which 引导的定语从句最为正式,用that的次之,而省略了关系代词that 或 in which 的, 反而显得更自然,最为常用.如下面三句话所示,其意义相同. I like the way in which he talks. I like the way that he talks. I like the way he talks. 如果怕弄混淆，下面的可以不看了 另外，在当代美国英语中,the way用作为副词的对格,"the way+从句"实际上相当于一个状语从句来修饰全句. the way=as 1)I'm talking to you just the way I'd talk to a boy of my own. 我和你说话就象和自己孩子说话一样. 2)He did not do it the way his friend did. 他没有象他朋友那样去做此事. 3)Most fruits are naturally sweet and we can eat them just the way they are ----all we have to do is clean or peel them . 大部分水果天然甜润,可以直接食用,我们只需要把他们清洗一下或去皮. the way=according to the way/judging from the way 4)The way you answer the qquestions, you must be an excellent student. 从你回答就知道,你是一个优秀的学生. 5)The way most people look at you, you'd think a trashman was a monster. 从大多数人看你的目光中,你就知道垃圾工在他们眼里是怪物. the way=how/how much 6)I know where you are from by the way you pronounce my name. 从你叫我名字的音调中,我知道你哪里人. 7)No one can imaine the way he misses her. 人们很想想象他是多么想念她. the way=because 8) No wonder that girls looks down upon me, the way you encourage her. 难怪那姑娘看不起我, 原来是你怂恿的
The way 的用法 "the way+从句"结构在英语教科书中出现的频率较高, the way 是先行词, 其后是定语从句.它有三种表达形式:1) the way+that 2)the way+ in which 3)the way + 从句(省略了that或in which),在通常情况下, 用in which 引导的定语从句最为正式,用that的次之,而省略了关系代词that 或in which 的, 反而显得更自然,最为常用.如下面三句话所示,其意义相同. I like the way in which he talks. I like the way that he talks. I like the way he talks. 一.在当代美国英语中,the way用作为副词的对格,"the way+从句"实际上相当于一个状语从句来修饰全句. the way=as 1)I'm talking to you just the way I'd talk to a boy of my own. 我和你说话就象和自己孩子说话一样. 2)He did not do it the way his friend did. 他没有象他朋友那样去做此事. 3)Most fruits are naturally sweet and we can eat them just the way they are ----all we have to do is clean or peel them . 大部分水果天然甜润,可以直接食用,我们只需要把他们清洗一下或去皮.
the way=according to the way/judging from the way 4)The way you answer the qquestions, you must be an excellent student. 从你回答就知道,你是一个优秀的学生. 5)The way most people look at you, you'd think a trashman was a monster. 从大多数人看你的目光中,你就知道垃圾工在他们眼里是怪物. the way=how/how much 6)I know where you are from by the way you pronounce my name. 从你叫我名字的音调中,我知道你哪里人. 7)No one can imaine the way he misses her. 人们很想想象他是多么想念她. the way=because 8) No wonder that girls looks down upon me, the way you encourage her. 难怪那姑娘看不起我, 原来是你怂恿的 the way =while/when(表示对比) 9)From that day on, they walked into the classroom carrying defeat on their shoulders the way other students carried textbooks under their arms. 从那天起,其他同学是夹着书本来上课,而他们却带着"失败"的思想负担来上课.
The way的用法及其含义（三） 三、the way的语义 1. the way=as（像） Please do it the way I’ve told you.请按照我告诉你的那样做。 I'm talking to you just the way I'd talk to a boy of my own.我和你说话就像和自己孩子说话一样。 Plant need water the way they need sun light. 植物需要水就像它们需要阳光一样。 2. the way=how（怎样，多么） No one can imagine the way he misses her.没人能够想象出他是多么想念她！ I want to find out the way a volcano has formed.我想弄清楚火山是怎样形成的。 He was filled with anger at the way he had been treated.他因遭受如此待遇而怒火满腔。That’s the way she speaks.她就是那样讲话的。 3. the way=according as （根据） The way you answer the questions, you must be an excellent student.从你回答问题来看，你一定是名优秀的学生。 The way most people look at you, you'd think a trash man was a monster.从大多数人看你的目光中,你就知道垃圾工在他们眼里是怪物。 The way I look at it, it’s not what you do that matters so much.依我看，重要的并不是你做什么。 I might have been his son the way he talked.根据他说话的样子，好像我是他的儿子一样。One would think these men owned the earth the way they behave.他们这样行动，人家竟会以为他们是地球的主人。