【正文】 ，表示主觀感情或態(tài)度的形容詞，如good,kind,nice,clever,foolish,right。 Why not +動詞原形表達(dá)向某人提出建議為什么不……? 干嗎不……?例如：Why not take a holiday？干嗎不去度假？It39。特殊句型so as to（1） 表示目的；它的否定式是so as not to do。但若表示對比、對照關(guān)系時，則不能省略。Rather than ride on a crowded bus,he always prefers to ride a bike.（5） Why… / why not…：（6） help 可帶to，也可不帶to,help sb (to) do sth：（7） but和except：but前是動詞do時，后面出現(xiàn)的動詞用不帶to的動詞不定式。ought to沒有人稱和數(shù)的變化，后接動詞原形可以表示現(xiàn)在、將來或過去將來，由時間狀語或上下文決定。(2)與被修飾詞之間有動賓關(guān)系，如是不及物動詞，則需加介詞（例④）。m glad to see you.典型例題The chair looks rather hard,but in fact it is very fortable to ___.A. sit　B. sit on　C. be seat　D. be sat on答案：B.　如果不定式為不及物動詞，其后應(yīng)有必要的介詞。作狀語（1）目的狀語To… only to (僅僅為了),　in order to,　so as to,　so(such)… as to… (如此……以便……)He ran so fast as to catch the first bus.　他飛快地跑以便趕上第一班車。I found him lying on the ground.I found it important to learn.I found that to learn English is important.作表語不定式作表語表示具體動作或?qū)韯幼?；動名詞作表語表示抽象的一般行為。例句：I often see him go to school on foot.(禿頭不定式作賓語補足語) He is often seen to go to school on foot.(不定式作主語補足語，要帶“to”) Let him try He is let try again.(let的主補與賓補均用禿頭不定式)Find 特殊用法Find5)禿頭不定式作補語禿頭不定式， 即不帶“to”的不定式，其語法功能一般在句子中作賓語的補語（賓語補足語）。4)　there be+不定式常見動詞：believe,expect,intend,like,love,mean,prefer,want,wish,undrstandWe didn39。b.　We believe him to be guilty.我們相信他是有罪的。注意：疑問詞帶不定式在句中作成分時，謂語動詞用單數(shù)。2） 動詞+疑問詞+（3） 當(dāng)不定式作主語的句子中又有一個不定式作表語時，不能用It is… to…的句型(對)To see is to believe.　眼見為實。s very kind of him to help us.　他幫助我們，他真好。s so nice to hear your 。It is better to have loved and lost than never to have loved at ，比從未愛過要好。這一句式有時相當(dāng)于Sb is+形容詞+to do句式 ，如：It39。②It takes sb+some time+to doHow long did it take you to finish the work?你花了多少時間來完成這項工作？③It+be+形容詞+for sb+to doIt is difficult for us to finish writing the position in a quarter of an 。(2)用it作形式主語，把真正的主語不定式置于句后，常用于下列句式中。如：To get there by bike will take us half an 。如：①When to leave for London has not been decided yet. （不定式在句子中做主語）②Mr. Smith didn39。2) 完成式：表示的動作發(fā)生在謂語動詞表示的動作之前。s birthday party.（不定式作主語是被動語態(tài)to be invited是被邀請）It was impossible for lost time to be made up.（不定式作主語）I wish to be sent to work in the country.（不定式作賓語）Can you tell me which is the car to be repaired?（不定式作定語）He went to the hospital to be examined.（不定式作狀語）My work is to clean the room every day.（不定式作表語）在There be結(jié)構(gòu)中，修飾主語的不定式可用被動，也可用主動。定義（語態(tài)）動詞和參與此動作的主語之間關(guān)系的一個術(shù)語。s a great honour to be invited to Mary39。ll see you again.　我希望再見到你。He seems to be eating something.4)完成進(jìn)行式：She is known to have been wreaking on the problem for many years.一般在表示情緒的動詞后加to do也表將來疑問詞疑問詞who,what,which,when,where,whether,how后可接不定式構(gòu)成不定式短語，在句中作主語、賓語、表 語等。作主語動詞不定式作主語時，句子的謂語動詞常用單數(shù)，其位置有以下兩種：(1)把不定式置于句首。To save money now seems 。It is an offence to drop litter in the 。在不定式前的sb，可看作其邏輯主語。⑥不定式的完成式也可作句子的主語To have made the same mistake twice was 。the first,　the next,　the last,　the best,　too much,　too little,　not enoughIt39。（2） It39。注意：（1） 其他系動詞如，look，appear等也可用于此句型（2） 不定式作為句子成分時，動詞用單數(shù)形式。I happen to know the answer to your question.我碰巧知道你那道問題的答案。t make up my mind which to ，我都拿不定主意買哪一種。如：We think it quite important for us to learn a foreign language well.He feels it his duty to help the poor.I find it difficult to learn English well.作補語1) 動詞+賓語+不定式(to do)常見動詞：advise，allow，believe，cause，challenge，pel，declare，encourage，forbid，force，　find，hire，induce，instruct，invite，like，order，permit，persuade，remind，request，require，select，send，suppose，tell，train，urge例句：a.　Father will not allow us to play on the street.父親不讓我們在街上玩耍。3) to be +形容詞常見動詞：Seem,　appear,　be said,　be supposed,　be believed,　be thought,　be known,　be reported,　hope, wish,　desire,　want,　plan,　expect,　mean…The book is believed to be uninteresting.人們認(rèn)為這本書沒什么意思。Mary took him as her father .　瑪麗把他當(dāng)作自己的父親。說明：五看see/watch/notice/observe/look at；三使役have/make/let；兩聽hear/listen to；一感feel。此類動詞還有g(shù)et，have。④Our work is serving the people.⑤What he likes is taking a walk after supper.⑥The story told by is intere