句中有以下词的,直接在这些词后面加NOT:
1.BE动词(am/is/are/was/were)2.情态动词(can/may/must/need/should....)3.的在其后加NOT，构成时态和语态的助动词(has/have/will/be...)
如:
I can swim.-------I can't swim.
She will come to see me next week.-----She (will not)(或won't) come to see me next week.
如果没有以上的词,则句子为一般现在时或一般过去时的肯定形式,变否定句时,先将动词变为原形,在动词前面助动词DO(DOES/DID),并在助动词之后加否定词NOT.助动词要根据时态和人称选用相应的.一般现在时用DO/DOES,其中DOES用于第三人称单数主语,DO用于除第三人称单数之外的其它主语.DID用于一般过去时,不论人称.
例如:
He goes to school on weekdays.-----He (doesn't go) to school on weekdays.
We went shopping last Monday.-------We (didn't go) shopping last Monday.
We like watching TV.------We (don't like) watching TV.
另外,除了NOT ,还有一些具有否定意义的词,以上是基本的,先记住这些.以上这些词变疑问也是要提前的
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