通常是將否定詞not或never置于不定式之前,即構成not to do 或never to do 的形式,注意not和never一定要放在不定式符號to的前面,而不是其后面。如:
The doctor advised me not to smoke. 醫(yī)生勸我不要抽煙。
Father warned me never to drive after drinking. 父親警告我不要酒后開車。
【注】若不定式為完成式和被動式,否定詞應置于整個結構之前。如:
She pretended not to have seen him. 她假裝沒看見他。
It is nice not to be dependent on others. 不依靠別人是好的。
2. so as to do sth 和in order to do sth 的否定式
對于這兩個結構的否定式,通常是將否定詞置于不定式符號to之前,而不是置于整個結構之前或其他位置。如:
Study hard so as not to fail the exam. 努力學習,以免考試不及格。
He came in quietly in order not to wake his wife. 他輕輕進來,以免把他妻子吵醒。