不定式的主部件是動詞，自然也有時態(tài)，但僅有“三元”：一般式to do，進行式to be doing，完成式to have done。其實還有to have been doing，但在此歸入完成式。

不定式的一般式to do，從時態(tài)意義上來說主要用來表示將來，此時不定式動作后于謂語動作發(fā)生；進行式to be doing主要用來強調(diào)動作的正在進行，此時不定式動作與謂語動作同時發(fā)生；完成式to have done，主要用來表示過去，此時不定式動作先于謂語動作發(fā)生。

我們來看例題：

1. When he the door，he found his keys were nowhere.

A. would open B. opened C. had open D. was to open

2.—In many developed countries，the elderly have already outnumbered children.

—Yes，and China is reported through a similar process of population aging，and at a faster pace.

A. to go B. to be going C. going D. to have gone

3. I am proud with Tom in 1789.

A. having sailing B. sailing

C. to have sailed D. to sail

上述三題，第一題答案選D，意思是當(dāng)他就要開門，鑰匙卻無處尋了。是過去時間里的“將來”。第二題答案選B。意思是報道的時候，人口老齡化依然在進行中，因此選B比較恰當(dāng)，如果選D，則說明老齡化進程已經(jīng)結(jié)束，與題意不符。第三題有明顯的過去時間，答案可以立即鎖定C項。

相較于一般式和進行式，不定式的完成式在高考中出現(xiàn)幾率更高，做題時要避免與主句的完成時“重疊”，以下面兩例來說明：

4. Some of our industrial products have been said

advanced level.

A. to reach B. to be reaching

C. to have reached D. to have been reaching

5. Some of our industrial products may well be said

advanced level.

A. to reach B. to be reaching

C. to have reached D. to have been reaching

第四題中，主句謂語動作已經(jīng)使用了完成時have been said，那么此時后續(xù)不定式動作部分一般避免再重復(fù)使用完成時，因此此題可以立即排除CD兩項，而B項正在進行，意思不符，選定答案A項。而同一題稍作變化，即變成第五題，其答案必須選擇C項，在這一題中，由于沒有完成時重疊的情況，此時只要考慮不定式本身應(yīng)選擇的時態(tài)，C項表示產(chǎn)品已經(jīng)達到很高的水平，符合題意。

英語中，不定式完成時主要有這樣四種呈現(xiàn)方式：

第一，在諸如happen，see，appear，prove，pretend，seem等動詞后；

第二，在“主語 + be said + to have done/been”的結(jié)構(gòu)中，類似結(jié)構(gòu)有reported/thought/supposed/expected/believed/considered/known等；

第三，在諸如glad，happy，sad，disappointed，satisfied，sorry，surprised等形容詞后；

第四，在表虛擬的“be to have done”結(jié)構(gòu)中，以及表示“意圖，打算”之意的動詞如hope，wish，expect，think，suppose，want，plan，agree，mean，try等用過去時之時，后接不定時完成時做賓語的結(jié)構(gòu)中，此時表達想做而未做的事情，但這種結(jié)構(gòu)更多地用had hoped/expected...等來表達虛擬。例如：They wished to have finished the work in two hours. = They had wished to finish the work in two hours. 均表示結(jié)果并未做到。請看例題：

6. I don’t know whether you happen ，but I’m going to study in the USA this September.

A.to be heard B.to be hearing

C.to hear D.to have heard

7. A woman and three children are said in the traffic accident.

A. to be injured B. to have been injured

C. having been injured D. being injured

8. I’m glad a visit to him last week.

A. to pay B. to have paid

C. to be paying D. to have been paid

9.—You should have told her about the meaning of the gesture.

—I meant ，but I had some unexpected guests.

A. to do B. to have C. doing D. doing so

上述四個例題分別對應(yīng)四種不定式完成時的呈現(xiàn)方式，答案為DBBB，其中最后一題的B選項to have后亦有省略用法，整體表達一種虛擬的情況，符合后半句揭示的含義。

不定式的“三元”時態(tài)，整體上不難，但對于其中的完成時則要格外注意，高考的考頻還是很高的，考生要養(yǎng)成不定式也要考慮時態(tài)意義的習(xí)慣。

配套練習(xí)

1. He seems deeply，without noticing me pass.

A. to think B. think C. to be thinking D. thinking

2. China is known greatly in terms of its cultural values over the past few years.

A. to change B. having changed

C. changing D. to have changed

3. You can comfort yourself with the thought that you are not the only one in that way？

A. to be suffered B. to have suffered

C. who was suffered D. of those suffered

4. He claimed in the supermarket when he was shopping yesterday.

A. badly treated B. treating badly

C.to have been badly treated D.to treat badly

5. I happened with him when a ball hit him on the head.

A. to be talking B. to have talked

C. to talking D. to talk

6. The factory is said in a fire two years ago.

A. to have been destroyed B. to be destroyed

C. to destroy D. to have destroyed

7. You were silly not to your car.

A. to lock B. to have locked

C. locking D. having locked

8. The young man，whose goal is the game，has been practicing hard these days.

A. having won B. to win C.to have won D. won

9. Who do you think was generally considered

the lamps？

A. inventing B. to invent

C. to have invented D. having invented

10. The accused was reported that he had robbed the old lady of her gold necklace.

A.to admit B.to have admitted

C.to be admitting D. that she had admitted

11. Who would you like to charge of the job？ My teacher said here is the expression——have somebody do something.

A. have take B. have taken C. take D.be taking

12. In order to gain a bigger share in the international market，many state-run companies are striving

their products more competitive.

A. to make B. making

C. to have made D. having made

13. I would love to the party last night but I had to work extra hours to finish a report.

A. to go B. to have gone

C. going D. having gone

14. It remains whether Jim’ll be fit enough to play in the finals.

A. seen B. to be seen C. seeing D. to see

15. The Brazilians are proud of the 31th Olympic Games in Rio de Janeiro in 2016.

A. hold B. holding C. held D. to be held

16. Judging from his manners at the party，he doesn’t seem much education.

A. to receive B. to be receiving

C. to have received D. to have been received

17. Linda was the experiment a month ago，but she changed her mind at the last minute.

A. having to start B. to have started

C. to start D. to be starting

18. I’m sorry not last weekend.

A. to come B. to have come

C. to be coming D. coming

19. I’d love to the party last night，but I had to work extra hours to finish a report.

A. to go B. to have gone

C. to going D. to be going

20. The results were to yesterday，but we have heard nothing.

A. announce B. be announcing

C. be announced D. have been announced

參考答案：

1—20 CDBCA ABBCB AABBD CBBBD