英语作文论文写作中连词 “and”、“but”和“or” 的使用规则

连词是用来连接单词、短语或从句的词。最常用的连词包括“and”、“but”和“or”。连词包括三种类型：并列连词, 从属连词, 关联连词。

连词的种类

连词的种类	连词的作用	连词的例子
并列连词	连接在语法上对等的内容	for, and, nor, but, or, yet, so
从属连词	引出从属从句	because, if, although, since, until, and while
关联连词	成对出现，并连接在语法上对等的内容	either/or, neither/nor, not only/ but also

Contents

1 并列连词
2 从属连词
3 关联连词
4 以连词开头写句子
5 连词和逗号的联用规则

并列连词

并列连词连接在语法上对等的单词、短语或从句。常用的并列连词包括：for, and, nor, but, or, yet, so。可以采用“F.A.N.B.O.Y.S.”这个便于记忆的词头拼接词记住上述七个并列连词。

Example: This study investigates the effects of Drug A and the placebo on the patients.

Example: You can choose to take the test or write an essay to pass the class.

当使用并列连词连接两个独立分句时，在并列连词前面要加逗号。

Example: She was unhappy with the test results, yet she refused to take the test again.

Example: I have only been here for one week, so I know practically nothing.

错误: You should invite Mary, and Jane to the party.

正确: You should invite Mary and Jane to the party.

从属连词

从属连词可以把从句和主句连接起来。从属连词用来表示因果关系、对比、时间或地点的过渡或条件关系。最常用的从属连词包括：after, although, before, even though, if, in case, till, whenever, unless, while。

表示因果关系

表示因果关系的从属连词包括：because, since, as, due to, as if。

Example: I could not go to class because I did not feel good.

Example: Due to his poor attendance, the professor had to fail him.

表示对比关系

表示对比关系的从属连词包括：although, though, whether, while, even though。

Example: While she plans to go to Paris for spring break, he plans to go to Tokyo.

Example: Although he is much younger than me, he is much smarter than most of my classmates.

表示条件关系

表示条件关系的从属连词包括：if, unless。

Example: Unless you leave now, you will be late.

Example: If he decides to take the offer, he will have to move out soon.

表示时间或地点的过渡关系

表示时间或地点的过渡关系的从属连词包括：where, everywhere, after, until, as soon as, before。

Example: Don’t forget to clean your room as soon as you get home.

Example: This is the place where I grew up.

关联连词

关联连词是成对使用的单词，用来连接一个句子中的两个部分或使其彼此关联。最常用的关联连词包括：either/or, neither/nor, not only/but also。

在使用关联连词时，它们之间通常无需用逗号隔开。

错误: I will either have a sandwich, or salad for lunch.

正确: I will either have a sandwich or salad for lunch.

错误: Neither the boy, nor his brother want to help their mother.

正确: Neither the boy nor his brother want to help their mother.

但是，当关联连词（例如“not only/but also”）用于分隔两个独立分句时，连词前面应加逗号。

错误: Not only did she start playing the piano at a very young age but her mother also taught her to compose music.

正确: Not only did she start playing the piano at a very young age, but her mother also taught her to compose music.

以连词开头写句子

人们常说以连词开头写句子在语法上不正确。然而事实并非如此。虽然不建议在太多的句子开头使用连词（尤其在学术写作中），但适度使用是完全没有问题的，而且有些时候必须用连词开头写句子。

Example: She wanted to go home. But he did not want to.

Example: Although I do not like the restaurant, I will go if you want me to.

Example: Either this dress or that pair of pants is fine.

连词和逗号的联用规则

无论何种类型的连词，连词与逗号联用的规则都非常简单，即使用连词连接两个独立分句时，连词前面应该使用逗号。

Example: The professor explained the assignment in detail, but the students did not seem to understand it.

Example: The weather is nice, but I don’t think we should go on the picnic.

但是，当用连词连接一个独立分句和一个从属分句时，连词前面不应该使用逗号。

错误: The professor explained the assignment in detail, and gave out the workbook.

正确: The professor explained the assignment in detail and gave out the workbook.

错误: The weather is nice, but a little bit chilly.

正确: The weather is nice but a little bit chilly.

需要注意的是，使用逗号连接两个独立分句也有例外，即如用连词连接的两个独立分句都很短，则可以省略连词前面的逗号。

错误: I cooked, and he cleaned.

正确: I cooked and he cleaned.

在主句前的介绍性从句、短语或单词后面要用逗号。用于这些从句或短语的连词通常包括：after, although, as, if since, when, while。

Example: While I do my homework, you go do the dishes.

Example: If you do not want to go to the party, you can stay home.