動詞不定式在句子中可以用作賓語補足語，高中范圍內，常用的“動詞+賓語+不定式”的句子結構中。不定式作賓語補足語的有以下八種類型：(下列句子中劃線部分作賓語補足語)
一、許多動詞可跟一個賓語 + to do…構成句子，句中的不定式作賓語補足語;否定形式為“動詞+賓語+not to do…”。例如：
My boss told me to type out two letters.
分析：句中“My boss”做主語，“told”作謂語，“me”作賓語，劃線部分作賓語補足語。請看下面的句子。
They forbade her to leave the country.
Please remind me not to be late for the meeting.
高中范圍內，適用于“動詞+賓語+(not)to do…”的結構，不定式作賓語補足語的動詞有：advise，allow，ask，beg，cause，direct，encourage，expect，forbid，force，invite，order，permit，persuade，remind，re- quest，require，teach，tell，want，warn等。
二、有些動詞可跟“賓語+to be…”構成句子，句中的不定式作賓語補足語。例如：
I consider him to be the best candidate.
分析：句中“I”做主語，“consider”作謂語，“him”作賓語，劃線部分作賓語補足語。請看下面的句子。
I know him to be a liar.
I suppose him to be away from home.
高中范圍內，適用于“動詞+賓語+to be…”的結構，不定式作賓語補足語的動詞有：consider，declare，discover，feel，find，suppose等。
三、有些動詞(感官動詞和使動詞)后可跟不帶to的不定式構成句子，句中的不定式作賓語補足語。例如：
He saw her enter the room.
分析：句中“He”做主語，“saw”作謂語，“her”作賓語，劃線部分作賓語補足語。請看下面的句子。
She won’t let me do it.
I heard her lock the door.
We watched the children play games.
高中范圍內，適用于“動詞+賓語+do…”的結構，不定式作賓語補足語的動詞有：feel，have，hear，let，make，notice，observe，see，watch等。還有兩個詞組：listen to，look at.
注意:這類句子變為被動結構時，不定式前加to。請看下列句子，句中劃線部分作賓語補足語。例如：
A child was seen to enter the building.
She was often heard to sing this song.
四、help后的不定式可加to，也可不加to(美國人不加to時較多)，但被動結構中要加to。例如：
I’ll help you(to) push the cart.
分析：句中“I”做主語，“will help”作謂語，“you”作賓語，劃線部分作賓語補足語。
上句的被動語態為：You’ll be helped to push the cart.
五、有些“動詞+介詞”的結構后也可跟不定式構成句子，句中的不定式作賓語補足語。例如：
He shouted to me to come over.
分析：句中“He”做主語，“shouted”作謂語，“to”為介詞，“me”作賓語，劃線部分作賓語補足語。請看下列句子，句子的結構為“動詞+介詞+賓語+to do…”，劃線部分為不定式，作賓語補足語。請看下面的句子。
I depend on you to do it.
I am counting on you to help me through.
高中范圍內，適用于“動詞+介詞+賓語+to do…”的結構，不定式作賓語補足語的動詞有：shout to sb.to do，call on sb. to do，count on sb. to do，depend on sb. to do，wait for sb. to do等。
六、作賓語補足語的不定式，表示的動作在謂語所表示情況之前發生，就需要用完成形式：
He was known to have worked for the International Olympic Committee.
分析：句中“He”做主語，“was known”作謂語，使用了被動語態。由句意可知，“為國際奧委會工作”發生在前，“大家知道”發生在后。故不定式部分用完成形式，在句中作賓語補足語。請看下面的句子。
They are believed to have discussed the problem.
七、作賓語補足語的不定式，表示一個正在進行的動作時需用進行形式：
He is believed to be living in Mexico.
分析：句中“He”做主語，“isbelieved”作謂語，使用了被動語態。由于句子表達主語現在正在發生的情況，故用不定式的進行形式，句中劃線部分作賓語補足語。請看下列句子。
Thousands were reported to be working in concentration camps.
He is thought to be hiding in the woods.
間或不定式作賓語補足語也可用于完成進行時。例如：
She is said to have been doing this work for twenty years.
八、不定式作賓語補足語的被動形式：
he didn’t want her son to be taken away.
分析：句中“She”做主語，“didn’t want”作謂語，“her son”作賓語，由于“her son”與“take away”之間為被動關系，故用被動形式，句中劃線部分作賓語補足語。請看下列句子。
I’d like this room to be redecorated.
He didn’t wish the subject to be mentioned in the letter.
■練習：
1.They knew her very well.They had seen her ___ up from childhood.(1988全國)
A.grow B.grew C.was growing D.to grow
2.The teacher asked us ___ so much noise.(2003北京)
A.don’t make B.not make C.not making D.not to make
3.My advisor encouraged ___ a summer course to improve my writing skills.(2004北京)
A.for me taking B.me taking C.for me to take D.me to take
4.The flu is believed ___ by viruses that like to reproduce in the cells inside the human nose and throat.(2004上海)
A.causing B.being caused C.to be caused D.to have caused
5.-Is Bob still performing?
-I’m afraid not.He is said ___ the stage already as he has become an official.(2005江蘇)
A.to have left B.to leave C.to have been left D.to be left
6.The mother felt herself ___ cold and her hands trembled as she read the letter from the battlefield.(2006上海)
A.grow B.grown C.to grow D.to have grown
7.Energy drinks are not allowed ___ in Australia but are brought in from New Zealand.(2006上海)
A.to make B.to be made C.to have been made D.to be making
答案：
1.A 2.D 3.D 4.C 5.A 6.A 7.B
