写作中的并行结构

什么是平行的句子结构?

平行的句子结构是指在同一个句子中,单词、短语或从句具有相同的语法形式。平行句式能使句子自然流畅,常用于列举或比较各元素,造成一种排比效果。在学术论文中,各章节的标题也通常使用平行句式结构。

错误
I enjoy books, writing, and painting.
正确
I enjoy reading, writing, and painting.

上例中的两个句子均在动词后面开列几个宾语元素。第一句列出的元素是“books”、“writing”和“painting”。“writing”和“painting”具有相同的语法形式,即均为动名词;“books”则不是动名词,而是普通名词。因此,第一句就显得别扭和不均衡。第二句开列的元素是“reading”、“writing”和“painting”。这三个元素具有相同的语法形式,因此句子读起来非常自然流畅,给读者一种良好的节奏感。

错误
You can apply either by visiting the office or email.
正确
You can apply either by visiting the office or sending us an email.

在上例中,这两个句子是在比较两个不同的元素。第一句比较的两个元素是“visiting the office”和“email”。这两个元素具有不同的语法形式,即分别是动词短语和名词。第二句比较的两个元素是“visiting the office”和“sending us an email”,它们则具有相同的语法形式。

序列中的平行结构

如上所述,在开列的序列中的各元素应当具有相同的语法形式。这些元素可以是单词、短语或从句,通常用逗号分号连词相连接,例如“and”或“or”。

单词的平行序列

当开列的元素是单词时,要想使用并行结构,就需要确保各元素具有相同的单词类型。换言之,名词应该与其他名词并列,形容词应该与其他形容词并列,动词应该与其他动词并列。

错误
She bought apples, potatoes, and is going to buy oranges.
正确
She bought apples, potatoes, and oranges.
错误
We are looking for an editor who is organized, self-motivated, and has a good eye for detail.
正确
We are looking for an editor who is organized, self-motivated, and detail-oriented.

如果开列的元素是动词,它们必须具有相同的形式。例如,一个动词的不定式必须与其他动词的不定式并列,而不应与分词或动名词形式并列。

错误
I need to cook, showering, and study.
正确
I need to cook, shower, and study.

短语的平行序列

当动词按照一串序列形式排列时,通常以动词短语的形式出现。与单个动词的平行结构一样,动词短语的平行结构也必须具有相同的语法形式。换言之,不定式短语应该和其他不定式短语一起列出,分词短语应该和其他分词短语一起列出,动名词短语应该和其他动名词短语一起列出。

错误
Your primary roles are greeting clients, to answer the phone, and updating the company calendar.

在上例中,“greeting clients”和“updating the company calendar”都是动名词。然而,“to answer the phone”是不定式短语。如果将这个不定式短语改为动名词短语“answering phone calls”,句子结构就变得平行了,示例如下。

正确
Your primary roles are greeting clients, answering phone calls, and updating the company calendar.

从句的平行序列

上述平行原则也适用于动词从句,即所有元素必须具有相同的语法形式。

错误
The children were told that they should not run in the halls, that they should not chew with their mouths open, and to not use profanities.

在上例中,“that they should not run in the halls”和“that they should not chew with their mouths open”具有相同的语法形式。然而,“to use profanities”却不具备。为了采用平行结构,需要修改“to use profanities”,或修改其他两个从句,示例如下。

正确
The children were told that they should not run in the halls, that they should not chew with their mouths open, and that they should not use profanities.
正确
The children were told to not run in the halls, to not chew with their mouths open, and to not use profanities.

冒号后的平行列表

冒号后面的列表内容也必须在语法上保持平行一致。

错误
The fabricated composites were found to share three desirable characteristics: having a high resistance to heat, low brittleness, and high flexibility.
正确
The fabricated composites were found to share three desirable characteristics: high heat resistance, low brittleness, and high flexibility.

成对的平行结构

与上述列表或序列中的各元素一样,成对的两个元素也必须在语法上平行,即具有相同的语法形式。成对的元素可以用并列连词、关联连词或比较级连词连接。并列连词包括以下七个:and,or,nor,but,yet,so,for。这些连词都可以将元素配对。

错误
We went shopping and to bike.
正确
We went shopping and biking.

关联连词也可以连接句子中的成对单词。关联连词包括以下五个:either … or,neither … nor,whether … or,not only … but also,both … and。

错误
The samples can be collected with either a cotton swab or puncturing the epidermis with a needle.
正确
The samples can be collected with either a cotton swab or a needle.
正确
The samples can be collected by either swiping the inner cheek with a cotton swab or puncturing the epidermis with a needle.

在句子中进行比较的两个元素之间也必须平行。以下词汇可以用于比较:than,as,like,over。

错误
We decided to examine the samples individually rather than scanning them all at once.
正确
We decided to examine the samples individually rather than to scan them all at once.

标题和提纲中的平行结构

学术论文的章节标题应当具有相同的语法结构。虽然期刊在作者指南中对此问题通常并未明确规定,但在章节标题中采用平行结构有助于论文显得更为专业和更有条理。这条原则也同样适用于论文提纲。

错误
Symptoms and disease duration
Mortality rate is high worldwide
Transmission mechanism and the effect of immunizations
正确
Symptoms and disease duration
Mortality rates worldwide
Transmission mechanism and the effect of immunizations

主题中的平行结构

如果句子中的元素在语意上不一致或不相关,尽管它们在语法形式上相同,句子仍然是不平行的。换言之,句子中的所有元素都应该彼此清晰关联。

错误
We found that the experimental results agreed with the theoretical model and went out dancing in the city.

在上例中,在语法上,“found that the experimental results agreed with the theoretical model”与“went out dancing in the city”虽然具有相同的语法形式,但是,仍然看不出这两句话有什么逻辑上的关系。因此,为了真正实现平行结构,必须在这两句之间添加关联词汇,示例如下。

正确
We found that the experimental results agreed with the theoretical model, and to celebrate, we went out dancing in the city.