什么是连词？
连词：用来连接单词、短语、句子的词。
常见连词及其用法：
①both … and… ： … 和…，两者都，既……而又……
Both Sam and Tom are my brothers.山姆和汤姆都是我的兄弟。
②not only… but （also）…：不但…而且…
Not only she but also you can come to my house.不但她而且你也可以来我家。
Not only is he angry , but （also ) he is sad.他不但生气，而且难过。
③as well as 同，和
I like this dress as well as that one.这件和那件裙子我一样喜欢。
You as well as Mary must study.你和玛丽都得学习。
④either …or…：或…或，不是，就是
Either you or he has to work.不是你就是她需要工作。
neither nor：既不…又不…，两者都不……
Neither you nor she is wrong.你和他都没错。
⑤so… that / such …that：如此…以至于…
注：so是副词，后面接形容词或副词。
such是形容词，后面接名词。
He is so clever that he always get good grades. = He is such a clever boy that he always get good grades.他是如此的聪明，以至于每次都得到好成绩。
⑥no sooner… than = hardly… when：一…就
I had no sooner rang the bell than she opened the door. = I had hardly rang the bell when she opened the door.我一按铃，她就开门了。
注：no sooner, hardly 放在句首，主谓须倒装。
⑦as soon as一…就…
She began to cry as soon as her mother left. 他妈妈一走她就开始哭了。
⑧as long as= so long as：只要
I will love you as long as I live.只要我活着，就会一直爱你。
⑨in case+ 从句=in case of+ n. = if + 从句
In case it rains we should bring an umbrella. = We showed the bring an umbrella in case of rain. = If it rains, we should bring an umbrella.我们应该带把伞，以防下雨。
⑩as if = as though好像（从句用虚拟语气）
She sings as if she were happy.她唱得好像很开心。
11.so far as：据……所知
So far as I know, she is from Japan.据我所知，他是从日本来的。
