动名词作句子的主语或者宾语一. 动词-ing形式的构成：是在动词末尾加-ing 形式构成，因此又叫动词的-ing 形式。
如：do-doing, be-being, ask-asking, etc.否定形式：not+ -ing 构成二. 动词-ing形式不能单独作谓语，没有人称和数的变化，但可以有自己的宾语和状语，还有时态和语态的变化。
动名词：在句子中起名次作用，可作主，宾，表，定的成分。
1 The v–ing form used as subject:It is necessary to get water from wet to dry place.________________________________It cost nothing to wish for thing._________________________________________________2 .The v–ing form used as object1) v+objectHe likes helping others.只接v-ing作宾语的动词有：admit, allow, avoid, appreciate, consider, delay, escape, enjoy, finish, keep, imagine, mind, miss, practice, suggestHe suggested practising speaking English in and out of class.2) prep.+ object.只接v-ing作宾语的词组有give up, put off, insist on, look forward to, pay attention to, lead to, devote... to, make a contribution to, feel like, stick toHe has devoted his life to finding ways to grow more and more rice.三. 1.动名词和不定式作主语，一般都可以使用形式主语it，而将动名词或不定式放在句尾。
但是在下列句型中，一般宜用动名词：It’s no use doing …It’s no good doing…It’s a waste of time doing …例如：It’s no use going there today; he won’t be at home.It’s a waste of time arguing about it.而在It’s important/necessary/advisable/ essential/fitting … 这类句型中，只能用不定式，如：It’s important to learn foreign languages.2. 在allow, advise, forbid, permit后直接跟动名词作宾语，如果有名词或代词作宾语，则构成“ allow／advise／forbid／permit ＋名词／代词＋不定式（宾语补足语）”之形式。
如：We don't allow smoking here．We don't allow anybody to smoke here．3. 动词need, require, want意为“需要”时，后跟动名词的主动式或不定式的被动式作宾语，意义没有区别。
如：The window needs／requires／wants cleaning／to be cleaned．4. 在begin, continue, love, like, hate, prefer, intend, start 后用动名词和用不定式作宾语均可，意义没有多大区别。
5. 动词forget, go on, mean, regret, remember, stop, try, be used to, can't help后跟动名词和跟不定式区别较大，须注意: forget, regret, remember后跟动名词，动名词表示已经发生的动作；后跟不定式表示将要发生的动作。
try doing 试着做某事try to do 努力做某事be used to doing 习惯于做某事be used to do 被用来做某事can't help doing 禁不住做某事can't help to do 不能帮助做某事1.— Let's have a rest．—Not now. I don’t want to stop __________ yet．A. studyB. to studyC. for studyingD. studying2.— Let me tell you something about the journalists．—Don’t you remember ________ me the story yesterday？A. toldB. tellingC. to tellD. to have told3.It took the workmen only two hours to finish _______ my car.A. repairingB. repairC. to repairD. repaired4. Have you forgotten ___$1000 from me last month? Will you please remember ____ it tomorrow? A. borrowing; to bring B. to borrow; bringC. borrowed; bringingD. borrowing; bringing5.My brother keeps ___ me with my work.。
A. to helpB. helpC. helpingD. helped6. We should often practise ___ English with each other.A. to speakB. spokeC. speakD. speaking7. The story was so funny that we ___.A. couldn’t help laughB. can’t but laughC. couldn’t hel p laughingD. couldn’t help but to laugh8. Though it sounds a bit too dear (昂贵), it is worth ______.A. being boughtB. buyingC. to buyD. buying it9. He devoted his life to _____ the atomic theory.A. studyB. be studiedC. studyingD. have studied10.We are both looking forward to __ next week.A.going on vocation (休假)B. go on vocationC. be going on vocationD. have gone on vocation11. The microscope is used for__ minute (微小的) objects.A. examiningB. being examinedC. examinedD. examine12.Mike has got used ___ up late at night. (stay up)A. to sitB. XC. to sittingD. sitting13.Once the heart stops _____, death follows at once.A. beatingB. to beatC. being beatenD. to be beating14. We are now busy _____ for the examination.A. to prepareB. preparingC. preparedD. being prepared15. The patient must be separated to avoid (避免) ____ others.A. being infected(感染)B. infectingC. to infectD. infected16.Your clothes need ______.A. washedB. to be washedC. to washD. being washed17. _____ provides us with essential nutrients (营养), while ______ provides us with oxygen.A. To eat; breathingB. Eating; to breatheC. Eating; breathingD. Eaten; breathed18. All the staff on our company are considering _____to the city centre for the fashion show. A．to go B．goingC．to have gone D．having gone19. Peter received a letter just now ________ his grandma would come to see him soon.A．said B．says C．saying D．to say20. —Robert is indeed a wise man.—Oh, yes. How often I have regretted ______ his advice! (2007年安徽卷)A. to takeB. takingC. not to takeD. not taking。