科技英语 文体特点: 词义明确、结构严谨、文风比较朴素和单纯； 非英语母语作者的表达问题：  句子内容的连贯性,  论述的逻辑性,  语法的正确程度,  作者熟练使用语言表达论点的能力,  论文中各部分的组织结构是否层次分明, 等等

Sentence Structure 1600年，英语句子平均为40-60个单词，1900年为21个，1970年为17个，目前为12-17个。 重要规则：One idea per sentence http://www.bpa.gov/corporate/kcc/circuit/99ci/ci0299/writetoreach.shtml

读者对论文结构信息的预期 宏观层次：IMRD的论文构架； 微观层次  句子或段落的叙述要遵循一定的主线, 每个表达单元(语段或语域)的主题内容应明确、单一;  力求组织形式合理, 不同主题间要有起过渡作用的词语或句子；  语法上的主语和谓语必须紧密相连;  “先旧后新”： 将“旧信息”(前文提到过的)放在句子的开始位置, 将新信息置于句子的末尾

“先旧后新”：不仅可以逐步深入地表达作者的观点, 并且也符合读者的阅读预期(思路不致于中断) The use of land, water and minerals has increased more than tenfold during the past two centuries. Future increases in population and economic development will intensify this pressure. * Major environmental changes varying from disruption of local ecosystems to disturbance of the biosphere are the likely cumulative impacts of human activities.  第三句应更改为: The cumulative impacts of human activities are likely to lead to major environmental changes, varying from disruption of local ecosystems to disturbance of the biosphere.

先旧后新（1） Samples for 2-dimensional projection of kinetic trajectories are shown in Figure 7. The coil　states are loosely gathered while the native states can form a black cluster with extreme high　density in 2-dimensional projection plane. Kinetic trajectories are projected onto xx and yy variables in Figure 7. This figure shows two populated　states. One corresponds to loosely gathered coil states while the other is the native state with a high　density. 从第一句到第二句信息无法流动：“The coil states” 从何而来？ 修改: 新插入的第二句使每句均能从旧信息出发到新信息结束。1, 2句以“Figure”相连; 2, 3句之间以“two states”相连，新信息“coil states”则出现在第三句的后部分，环环相连，成为一整体

先旧后新（2） The accuracy of the model structures is given by TM-score. In case of a perfect match to　experimental structure, TM-score would be 1. 在第二个句子里，旧信息“TM-score”被埋在中间，被新信息“a perfect match to experimental structure”打断了。这里建议修改如下： The accuracy of the model structures is measured by TM-score, which is equal to 1 if there is　a perfect match to the experimental structure.

先旧后新、首句为段落主题 The enthalpy of hydrogen bond formation between the nucleoside bases 2-deoxyguanosine (dG) and 2-deoxycytidine (dC) has been determined by direct measurement. dG and dC were derivatized at the 5 and 3 hydroxyls with triisopropylsilyl groups to obtain solubility of the nucleosides in non-aqueous solvents and to prevent the ribose hydroxyls from forming hydrogen bonds. From isoperibolic titration measurements, the enthalpy of dC:dG base pair formation is 6.650.32 kcal/mol. We have directly measured the enthalpy of hydrogen bond formation between the nucleoside bases 2-deoxyguanosine (dG) and 2-deoxycytidine (dC). dG and dC were derivatized at the 5 and 3 hydroxyls with triisopropylsilyl groups; these groups serve both to solubilize the nucleosides in non-aqueous solvents and to prevent the ribose hydroxyls from forming hydrogen bonds. The enthalpy of dC:dG base pair formation is 6.650.32 kcal/mol according to isoperibolic titration measurements. 首句为整段的主题，第一句颠倒是为了使新信息“dG”和“dC” 在句子最后并强调他们，更好地跟下面一句衔接；第二句被分成两部分，这样每一部分只表达了一个观点。

先旧后新、首句为段落主题 Large earthquakes along a given fault segment do not occur at random intervals because it takes time to accumulate the strain energy for the rupture. The rates at which tectonic plates move and accumulate strain at their boundaries are approximately uniform. Therefore, in first approximation, one may expect that large ruptures of the same fault segment will occur at approximately constant time intervals. If subsequent main shocks have different amounts of slip across the fault, then the recurrence time may vary, and the basic idea of periodic main shocks must be modified. Large earthquakes along a given fault segment do not occur at random intervals because it takes time to accumulate the strain energy for the rupture. The rates of strain accumulation at the boundaries of tectonic plates are approximately uniform. Therefore, nearly constant time intervals (at first approximation) would be expected between large ruptures of the same fault segment. [However?], the recurrence time may vary; the basic idea of periodic main shocks may need to be modified if subsequent main shocks have different amounts of slip across the fault. 第1段: 第一句里的旧信息（rate of strain accumulation)并没有放在第二句的开始, 到第3句就不明白这段到底要讲什么了 新段着重阐明了地震的发生频率, 以前描述过的旧信息-理解这段的关键。

力求句子结构紧密, 表达准确、简短、清晰 (1) 句子中相关部分应尽可能地紧邻: 修饰语与被修饰对象的关系应明确、尽量相邻, 等. (2) 删除there be等冗词, 使句子更为紧凑. 如:  In most specimens there is more biotite than hornblende.  Most specimens contain more biotite than hornblende. (3) 尽量使用并列的动词代替叠加的名词, 以避免句子冗长、笨拙. 如:  Techniques used for identification and quantitation…  Techniques used to identify and quantify…

主语和行为动词紧密相邻 如果动词和主语之间相隔太远，阅读就会被寻找动词打断： The smallest URFs (URFA6L), a 207-nucleotide (nt) reading frame overlapping out of phase the　NH2-terminal portion of the adenosinetrip hosphatase (ATPase) subinit 6 gene has been identified as the　animal equivalent of the recently discovered yeast H+-ATPase subunit 8 gene. The smallest of the URFs is URFA6L, a 207-nucleotide (nt) reading frame overlapping out of phase the NH2-terminal portion of the adenosinetriphosphatase (ATPase) subinit 6 Gene; it has been identified as the animal equivalent of the recently discovered yeast H+-ATPase subunit 8 gene. 避免头重脚轻：短的主语紧跟着动词, 加上长的宾语

保持句子成分（或词语）之间在人称、数、性等方面的一致, 尤其要注意主谓一致 (1) 不可数名词、集体名词的谓语动词取决于具体的语境. 如: data, number等单词的使用； (2) 由what, every, each, no, neither, one等引导的单数主语必须配合单数谓语动词； (3) 单数主语后面紧跟以with, together with, along with, including, in addition to, as well as等引导的短语时, 必须配合单数谓语动词； (4) 有关代词使用中的指代一致和数的一致

代词的使用: 指代要清楚 their = genesis and evolution of weather systems (?) Since potential vorticity (PV, defined as…) was first introduced by Ertel [1], it has been extensively used to study the genesis and evolution of weather systems for several decades [2-9] and has enhanced the understanding of the dominant physical processes responsible for their formation and growth. Its conservation in a frictionless adiabatic flow and its invertibility in a balanced system has been key to this. it = potential vorticity their = genesis and evolution of weather systems (?) this = ? A modeling study of the moist vorticity vector associated with aheavy rainfall event in North China

句子的重点通常在句尾（1） URFA6L has been identified as the animal equivalent of the recently discovered yeast H+-ATPase subunit 8 gene. Recently discovered yeast H+-ATPase subunit 8 gene has a corresponding animal equivalent gene URFA6L. 前面的句子是关于一个最近发现的酵母基因，而第二句则着重强调了它有一个和动物一致的基因

句子的重点通常在句尾（2） The enthalpy of hydrogen bond formation between the nucleoside bases 2-deoxyguanosine (dG) and2-deoxycytidine (dC) has been determined by direct measurement. 这个句子看起来是在强调“direct measurement”, 这似乎不是作者的目的. 颠倒一下会使句子更简短，同时避免了头重脚轻： We have directly measured the enthalpy of hydrogen bond formation between the nucleoside bases 2-deoxyguanosine (dG) and 2-deoxycytidine (dC). 句尾是读者对该句最后的印象：把最好的，最重要的，和想要读者记住的内容放在句尾

对于主动语态或被动语态、第一人称或第三人称的使用应自然、妥当, 不应刻意回避或追求采用某个特定的人称或语态  Samples were collected from several localities. (Samples为叙述的主题)  We collected samples from several localities. (以研究过程为叙述主题)  Bees disperse pollen. (描述bees的论文)  Pollen is dispersed by bees. (描述pollen的论文)

优先使用主动语态  The fact that such processes are under strict stereoelectronic control is demonstrated by our work in this area. (18个词)  Our work in this area demonstrates that such processes are under strict stereoelectronic control. (14个词) 句子的主语在逻辑上要清楚、连贯, 避免在同一句子或段落内部改变语态形式(以免冗长和迂回)  These vugs carry no gold and the tenor of the vein has not been affected by them.  These vugs carry no gold and do not affect the tenor of the vein.

悬垂修饰(Dangling modifier) 悬垂修饰：指句子中动词短语与句子主语没有联系, 即: 动词短语的逻辑主语与主句的主语不相一致. (1) 悬垂分词 错: Using the procedure described previously, the partition function can be evaluated. 对: Using the procedure described previously, we can evaluate the partition function. 错: When confronted with these limitations, the experiments were discontinued. 对: When confronted with these limitations, we discontinued the experiments.

悬垂修饰(Dangling modifier) (2) 悬垂动名词 错: After determining the mapping of Ai from L1 to Lp, the next array dimension can be processed in the same way. 对: After determining the mapping of Ai from L1 to Lp, we can process the next array dimension in the same way. (3) 悬垂的不定式 To determine its respiratory quotient, the organism was… (显然, the organism不能来determine…) (4) 悬垂的省略从句

独立结构 (Absolute construction)  Assuming that distance d is induced by the norm, M is a symmetrical and positively defined matrix.  Taking this value as an upper limit, the two shortest distances are sometimes too long for incipient hydrogen bonds.  To prepare compound 2, the method of Garner was followed. 在独立结构成分中经常出现的引导性动词有: concerning; considering; failing; given; judging; provided; providing; regarding; 等等

英文表达注意事项 (1) Very long sentences In English, the main idea and each supporting idea is typically written in separate sentences. One can usually recognize a very long sentence by its length – sixty words or more. However, sentences of smaller lengths can also be too long if they contain multiple statements that confuse the main idea.

Too long: The gear transmission is grade seven, the gear gap is 0 Too long: The gear transmission is grade seven, the gear gap is 0.00012 radians, the gear gap has different output values corresponding to any given input value, nonlinearity of the gear gap model can be described by using the phase function method, the existing backlash block in the non-linear library of the Matlab/zdimulink toolbox can be used, the initial value of gear gap in the backlash block is set to zero. Correct: The gear transmission is grade seven. The gear gap, which is 0.00012 radians, has different output values corresponding to any given input value. The nonlinearity of the gear gap model can be described by using the phase function method. The existing backlash block in the non-linear library of the Matlab/zdimulink toolbox can be used; the initial value of gear gap in the backlash block is set to zero.

Too long: According to the characteristic of fan-coil air-conditioning systems, this paper derives the cooling formula of fan-coil units based on the heat transfer theories and puts forward a new method to gauge cooling named Cooling Metering on the Airside, which can monitor the individual air-conditioning cooling consumption during a period of time by detecting the parameters of inlet air condition –temperature and humidity – of the fan-coil air-conditioning system as well as the parameters of inlet cooling water provided by the chiller. Correct: This paper derives the cooling formula of fan-coil units based on the characteristics of fan-coil air-conditioning systems and heat transfer theories, and puts forward a new method to gauge cooling called Cooling Metering on the Air-side. The new method can monitor individual air-conditioning cooling consumption during a period of time by detecting the condition of inlet air – temperature and humidity – of the fan-coil air-conditioning system as well as the parameters of the inlet cooling water provided by the chiller.

Too long: …where m is the mass of the heavy disk mounted at the mid-span of a massless elastic shaft, e is the eccentricity of the mass center from the geometric center of the disk, φ is the angle between the orientation of the eccentricity and the ξ axis, ξ k and η k are the stiffness coefficients in two principal directions of shaft respectively, c is the viscous damping coefficient of the shaft and the disk, ω is the rotating speed, … Correct: Where m is the mass of the heavy disk mounted at the mid-span of a massless elasticshaft, e is the eccentricity of the mass center from the geometric center of the disk, φ is the angle between the orientation of the eccentricity and the ξaxis, ξ k and η k are the stiffness coefficients in the two principal directions of the shaft, c is the viscous damping coefficient of the shaft and the disk, ω is the rotating speed,

Main idea at the beginning 英文表达注意事项 (2) Main idea at the beginning Bring the main idea to the beginning of the sentence stating any purpose, locations, reasons, etc., afterwards. Incorrect: To ensure sheet metal quality as well as assembly quality, CMMs are widely used in automotive industry production. Correct: CMMs are widely used in automotive industry production to ensure sheet metal quality as well as assembly quality.

‘In this paper’, ‘in this study’ 英文表达注意事项 (3) ‘In this paper’, ‘in this study’ In some papers written by Chinese, these phrases can occur as much as twice per page. In papers written by native English writers these phrases are reserved for primarily two uses. Actually, the reader is aware that the work presented is by the author (unless the author states otherwise) so there is no reason to repeat these phrases.

The ‘study (or research)’ is the work the author(s) did. The paper is the mode to present this work and is what the reader is holding/reading. (This paper present…) Awkward: In this paper, IDEAS was used to …. Correct: In this study, IDEAS was used to…. Awkward: In the paper, a SZG4031 towing tractor is used as the sample vehicle, it components … Correct: In this study, a SZG4031 towing tractor is used as the sample vehicle, it components …

英文表达注意事项 (4) at home / abroad International papers should not use location dependant terms such as ‘at home’, ‘abroad’, ‘here’, ‘our country’ because the reader most likely is not Chinese and not in China. at home, our country = in China abroad = outside China overseas = outside the mainland of China

Arabic Numbers Should never be used at the beginning of sentences 英文表达注意事项 (5) Arabic Numbers Should never be used at the beginning of sentences Should not be used to give general information  11 parameters were selected for the experiment.  Eleven parameters were selected for the experiment.  All 3 studies concluded that the mean temperature should be 30 C.  All three studies concluded that the mean temperature should be 30 C.

Avoid redundancy research work = research / work 英文表达注意事项 (6) Avoid redundancy research work = research / work limit condition = limit / condition sketch map = sketch / Map layout scheme = layout / scheme simulation results = results / simulation calculation results = results / calculation

a, an, the (1) Omitted where they are required; 英文表达注意事项 (7) a, an, the (1) Omitted where they are required; (2) Used where they are not needed (3) Used wrongly in place of the correct article. Incorrect: Figure 2 shows the distribution of relative velocity on surface of main and splitter blades. Correct: Figure 2 shows the distribution of relative velocity on the surface of the main and splitter blades. Incorrect: The software PowerSHAPE is chosen to be a 3D modeling tool; … Correct: The software PowerSHAPE is chosen to be the 3D modeling tool; …

冠词和名词用法示例 Nuclear magnetic resonance (NMR) has played a extremely important role in structural identification of organic compound. Because it can resolve molecular structure with high precision without destroying molecular biological function, it is expected for biological analysis. However, due to diversity and complexity of biological molecule, large amount of structural information are still unknown. Nuclear Magnetic Resonance (NMR) has played an extremely important role in the structural identification of organic compounds. Because NMR can resolve …, it is expected for the biological analysis. However, because of the diversity and complexity of biological molecules, much structural information remains unknown.

U.K. English vs. U.S. English 英文表达注意事项 (8) U.K. English vs. U.S. English sulphide sulfide colour color analyse analyze catalogue catalog Most word processors have built-in spelling (and grammar) checkers. Use them! They are not always perfect, but will help erase common problems