not的用法
一 . not 的位置
1. not 可以置于 be 动词、情态动词及助动词之后，构成否定句。
除了 am 和 not ， may 和 not 不能合写之外，其余的一般都可以和 not 合写。例如：
（ 1 ） He is not （ isn't ） a man to give things up easily.
他不是一个随便放弃的人。
（ 2 ） He can not （ cannot, can't ） speak Chinese as well as Tom.
他的汉语没有汤姆讲得那么好。
（ 3 ） You did not （ didn't ） know how worried I was about you at that time.
你不知道那时我是多么地担心你！
注：
had better do sth,
would rather do sth,
would like to do sth.
be about to do sth. 的否定形式分别是
had better not do sth,
would rather not do sth,
would like not to do sth.
be about not to do sth ；
used to 的否定形式是 usedn't to 或 didn't use to 。例如：
（ 4 ） You'd better not eat too much chocolate, or you'll get too fat.
你最好不要吃太多的巧克力，否则身体会发胖的。
（ 5 ） I would rather not accept his present.
我宁愿不要他的礼物。
2. not 可以置于分词、不定式和动名词之前，构成非谓语动词的否定形式。例如：
（ 1 ） Not having received any reply from Tom, Mary decided to write to him again.
由于没收到汤姆的回音，玛丽决定再 给他写封信。
（ 2 ） He kept silent over the matter in order not to lose his job.
他对这件事保持沉默是为了不丢掉他的这份工作。
（ 3 ） She was very upset for not having been invited to the party.
她因没有被邀请去参加晚会而感到很伤心。
3. not 的位置转移：
（ 1 ）主句的主语是第一人称 we 和 I ，谓语动词是 think, believe, imagine, suppose 等时，常将其后宾语从句中的否定词 not 前移至这些动词之前。这种语法现象称之为否定转移。例如：
① I don't think the film is intended for children.
我觉得这部电影不适合儿童看。
② We don't believe he stole money from the stop.
我们相信他不会偷那店铺里的钱。
（ 2 ）若用“ It is / was … that …”去强调 until 引导的状语从句，主句中又有否定词 not ，则常将 not 和 until 放在一起加以强调。例如：
It was not until he told me that I had an idea about it.
直到他告诉我，我才明白这件事。
（ 3 ）当 not until, not only （… but also …）， not for a moment, not a single ……等位于句首时，有关分句的主语和谓语要倒装。例如：
① Not only has he been to London but also he worked there for a time.
他不仅去过伦敦，而且还在那里工作过一段时间。
（ not only 后面的分句中的主语和谓语倒装， but also 后面分句中的主语和谓语不倒装。）
