一般式 to do to be done 　进行式 to be doing 　　　　　/ 　完成式 to have done to have been done 　完成进行式 　　to have been doing / A. 1. 不定式的一般式 : 不定式的一般式表示的动作通常与主要谓语的动作同时或几乎同时发生，或是在它之后发生。

2. 不定式的进行式: 不定式的进行式表示正在进行的动作。

　3. 不定式的完成式: 不定式的完成式表示的动作在谓语表示的动作之前发生。

B. 不定式的被动形式 当不定式逻辑上的主语是这个不定式表示的动作的承受者时，不定式一般要用被动形式。

C. 不定式的否定形式 不定式的否定形式由not或never加不定式构成。

即景活用：

1) The novel is said ____________into many languages. 据说这部小说已被译成多种语言。

2) It happened _________________when I got there. 我到达那里的时候，天碰巧在下雨。

3) The engine just won't start. Something seems ___________________ (go) wrong with it.

III.不定式的省略

1) They had nothing to do but move.

2) I don't go swimming now but I used to.

3) ---Have you told Allen about the concert?

---Sorry, but I ought to have.

归纳拓展：

1. 不定式在介词but, expect后面时，若这些介词前有实义动词do的各种形式，则后接不带to的不定式，否则带to.

2. 在同一句或联系紧密的对话中，为了避免重复，作宾语或补语的不定式再次出现时，to后的内容常承前省略(只保留to即可)。

注意: 但如果承前省略的不定式有助动词have或be的任何形式，后应该保留原形be或have。

即景活用：

1) He didn't do anything but___________________(抱怨).

2) Susan is not what she____________________(Susan不再是过去的样子).

达标检测

1) The ability ______________________(express)an idea is as important as the idea itself .

2) I send you 100 dollars today, the rest ______________________(follow) in a year.

3) The airport ________________(complete) next year will help promote tourism in this area.

4) There are still many problems __________________________(solve) before we are ready for a long stay on the Moon.

5) With so much work_________________(do), I can't go swimming with you.

6) Your cousin is said ____________________(design)a new computer programme recently, but do you know when he will finish it?

7) He claimed ___________(treat; bad) in the market when he was doing shopping yesterday.