生命科学背景的作者常犯的英文文法错误种类繁多。这些作者们犯错的原因往往是由于英文并非他们的第一语言，因此对英文的接触较为有限。Essay写作乃是一项庞大的任务，而语言问题常会成为书写的障碍。写作并且发表Essay对研究者而言极为重要，但Essay稿件中如果有语言或文法错误，就可能遭到科学期刊退稿。基于留学作业网(www.cieae.net)多年的留学作业辅导经验，在此列出十项生命科学类Essay作者常犯的文法错误。在下列内容中，我们将以实例阐释这些错误。

　　第一项：冠词

　　英文中共有三个冠词(a、an，和the)。这三个冠词分成两类：不定冠词(a、an)和定冠词(the)。决定正确的冠词通常相当复杂。先区分定冠词和不定冠词后，还须依照后面所接名词的发音，而非拼法，来选择最恰当的不定冠词。

　　作者常犯的错误之一就是在列出一串词语或名词片语时，在每个词之前都重复加上定冠词(the)。

　　在一长串需要定冠词的名词片语中，只要在第一个词语之前加上定冠词，后面所有的词语都不必再加冠词。

　　范例：

　　错误的用法：We focus on the parameters of the representative frequency,the composition of sounds and the sequence complexity.

　　正确的用法：We focus on the parameters of the representative frequency,sound composition,and sequence complexity.

　　错误的用法：No effects were observed on the cell growth,the cell proliferation,the cell cycle distribution,and the gene expression.

　　正确的用法：No effects were observed on the cell growth,cell proliferation,cell cycle distribution,and gene expression.

　　第二项：使用连字号

　　连字号在写作时有多种功能。它会被使用的地方还不少，如：含有数值或单位的修饰语(例如5-g dose)、完整拼出的分数(例如two-third part of this area)、后半部含有现在或过去分词的复合修饰语(例如seizure-inducing drugs)，它也可用来避免字母重复造成的视觉混淆(例如meta-analysis)。

　　然而，作者们经常在不必要的情况下使用连字号，因而造成错误。列举部分错误如下：

　　当拉丁文片语作为形容词的时候(例如in vitro test and post hoc hypothesis)，则不应该使用连字号。

　　范例：

　　错误的用法：A cloned gene makes it possible to synthesize the encoded protein by in-vitro transcription and translation.

　　正确的用法：A cloned gene makes it possible to synthesize the encoded protein by in vitro transcription and translation.

　　科学术语，如做为修饰语的字母，连字号只使用在当术语做为形容词片语时。

　　范例：

　　错误的用法：The majority of T-cells bear the T-cell receptor(TCR)which recognizes foreign antigen peptides.

　　正确的用法：The majority of T cells bear the T-cell receptor(TCR)which recognizes foreign antigen peptides.

　　第三项：时态

　　文法上，时态是用来表示时间，通常使用特定的动词形式。在同一句中，动词时态应保持一致。时态前后不一致是一项常见的错误。

　　范例：

　　错误的用法：The burst pulses were separated when the density of peaks is higher than 0.4.

　　正确的用法：The burst pulses were separated when the density of peaks was higher than 0.4.

　　错误的用法：We mapped the 3-kb transcript of the locus and had determined that it contains four exons and two introns.

　　正确的用法：We mapped the3-kb transcript of the locus and determined that it contains four exons and two introns.

　　第四项：平行结构

　　平行结构是指以相同的文字型态表示两个或两个以上的概念同等重要。此结构可使用于单字、片语或子句，常以对等连接词「and」或「or」连接组成。

　　这是研究者常见的错误类型之一。在平行结构中，名词需搭配名词、介系词片语配介系词片语、分词配分词、不定词配不定词，且子句配子句。

　　范例：

　　错误的用法：The sbcC gene was cloned,mapped,and sequencing was performed.

　　正确的用法：The sbcC gene was mapped,cloned,and sequenced.

　　错误的用法：We investigated the effects of the drug on cell proliferation and cell cycle distribution and gene expression was profiled.

　　正确的用法：We investigated the effects of the drug on cell proliferation and cell cycle distribution and performed gene expression profiling.

　　第五项：主词动词不一致

　　在英文中，动词应永远与主词一致。主词动词不一致是另一项研究者常犯的错误。如果主词是单数，则动词也应该为单数;而如果主词是复数，则动词也应为复数。

　　范例：

　　错误的用法：The foraging probability of fishes can be elevated when the deep scattering layer rise to the surface water.

　　正确的用法：The foraging probability of fishes can be elevated when the deep scattering layer rises to the surface water.

　　The verb(rises)should agree with the subject(singular:the deep scattering layer).

　　错误的用法：Three groups were separated when the resources in the same group is from the same origin.

　　正确的用法：Three groups were separated when the resources in the same group were from the same origin.

　　第六项：负向转移

　　负向转移意指在同一句中使用两个否定词以表示对比。例如，作者经常错误地成对使用although…but。由于这些词语意思相同，它们不应同时出现在句中，否则将形成赘字。

　　范例：

　　错误的用法：Although VDAC1 is ubiquitinated following mitochondrial depolarization,but VDAC2 is not ubiquitinated.

　　正确的用法：Although VDAC1 is ubiquitinated following mitochondrial depolarization,VDAC2 is not.

　　错误的用法：Because human immunodeficiency virus(HIV)type 1 infection is efficiently transmitted by sexual intercourse,so the sexual behaviors of some individuals have placed them at high risk for infection.

　　正确的用法：Because human immunodeficiency virus(HIV)type 1 infection is efficiently transmitted by sexual intercourse,the sexual behaviors of some individuals have placed them at high risk for infection.

　　第七项：撇号

　　撇号是一个标点符号。在某些使用拉丁或其他字母的语言中，它也可作为变音符号。它在英文中有三个功能：标示省略了一个或多个字母、标示所有格，以及标示事物为复数形式。

　　许多人会将无生命的受词套用所有格，应该避免这种用法。

　　范例：

　　错误的用法：The coordinated gene's expression networks in numerous physiological,developmental,and metabolic processes.

　　正确的用法：The coordinated expression of gene networks in numerous physiological,developmental,and metabolic processes.

　　医学人名名词后的所有格应该一律删除。

　　范例：

　　错误的用法：Klinefilter's syndrome is the most common genetic cause of male infertility.

　　正确的用法：Klinefilter syndrome is the most common genetic cause of male infertility

　　第八项：介系词

　　介系词标示出名词或代名词和句中其他字或其他部分的之间关系。它的英文preposition(pre-position，置于前方)源自它通常位于名词或代名词之前。误用介系词常常会导致改变句意。

　　范例：

　　错误的用法：The consensus amino acid sequence for phosphorylation by cyclin Cdk4 is different than that for phosphorylation by cyclin Cdk2.

　　正确的用法：The consensus amino acid sequence for phosphorylation by cyclin Cdk4 is different from that for phosphorylation by cyclin Cdk2.

　　错误的用法：The histological changes into lung biopsies induced after 30 weeks of therapy.

　　正确的用法：The histological changes in lung biopsies induced after 30 weeks of therapy

　　第九项：逗号连句

　　逗号的作用是连接句中一连串的想法。然而，一般人常以为逗号就是要用在需要停顿的地方。这并不完全错误，但可能会误加不必要的逗号而引起混淆。

　　在两个完整想法(完整句或子句)之间误加逗号就会产生逗号连句，而逗号连句将产生「连写句run-on sentence」。

　　范例：

　　错误的用法：They are the top predators of the marine ecosystem,using a wide range of habitat to obtain sufficient food resources.

　　正确的用法：They are the top predators of the marine ecosystem that use a wide range of habitat to obtain sufficient food resources.

　　错误的用法：The long-duration recording facilitates the examination,of the occurrence patterns of fishes.

　　正确的用法：The long-duration recording facilitates the examination of the occurrence patterns of fishes.

　　第十项：名词复数化

　　名词复数化也是一个很常见的文法错误。在名词后面加上「s」或「es」即可将名词变成复数。第一种错误是多此一举，将「当形容词用的名词」变成复数。

　　范例：

　　错误的用法：Nine-weeks-old albino normal(non-cancerous)mice belong to the strain Mus musculus.

　　正确的用法：Nine-week-old albino normal(non-cancerous)mice belong to the strain Mus musculus.

　　一般而言，即便当形容词用的名词修饰复数名词，它本身并不需加复数(但有部分例外)。

　　第二种错误是复数化某些常见的不可数名词，而这些名词并没有复数形(例如research和evidence)。

　　范例：

　　错误的用法：Examination of lacY and lacZ expressions in homozygotes to reveal their functions.

　　正确的用法：Examination of lacY and lacZ expression in homozygotes to reveal their functions.

　　在科学写作中，特别是在指称基因或蛋白表达时，「表达expression」这个词可当单数或复数。若要强调该词为复数，则可采用「表达水平expression levels」或其他类似的片语。请注意在其他非技术领域，表达是一个可数名词。