不定式基本形式：to+動詞原形十性，其中有一部分不定式是沒有to的坏逢，那么哪些情況下与涡，不定式沒有to呢峭梳？
1、感官動詞這幾個感官動詞feel ,hear ,smell,look,在主動語態(tài)里后接動詞原形(無to)虱而。例如：I saw him sing. I heard you play the piano. He feels him fly. I watched the girl cross the road.
2筏餐、使役動詞使役動詞let、 have 牡拇、make后接不定式沒有to.
例如：You must? have? your son see his own mistakes. Let me go. Don't make her? laugh.
3胖烛、在why not 后沒有to，基本結構可記憶why not do 更容易
(1)表示提建議
例如：
Why not go with him?Why not have a rest?
（2）表示認為沒有必要例如：Why worry. you can't do anything about it ?Why waste?
4诅迷、had better do 最好做…和would rather do 寧可做…后面的不定式沒有to. '
You'd better drink the water now. or you will not be fine. I would rather go? by? bus now
5、Will? you? please do 征求意見众旗，求助罢杉。例如：Will? you? please open the? window?Will? you? please give? me? a hand ?
6、help 可以有to 也可以沒有toHelp the boy to carry? the? heavy box. Help the old man water the? flowers.
7贡歧、can't … but …滩租，do nothing …but…結構中沒有to
例如：We can't choose but obey
He can't help but feel sorry
for her.
We do nothing but wait.
以上是常用的不定式中不帶to的幾種情況，但是如果在被動語態(tài)中還是有to的利朵，例如：I saw her? danceShe was seen to danceMake her laugh She was made to laugh 這些情況在被動語態(tài)里在詳細講解律想。
