初三英語上冊知識點：動詞不定式.doc

初三英語上冊知識點：動詞不定式一. 定義：動詞不定式是非謂語動詞的一種，它沒有人稱和數(shù)的變化，在句子中不能獨立作謂語，但它仍保持動詞的特點，既可以有自己的賓語和狀語。同時動詞不定式又具有名詞、形容詞、副詞的特征，在句中可以作主語、表語、賓語、賓語補足語、定語和狀語。二. 動詞不定式的構(gòu)成：to+動詞原形三. 動詞不定式作賓語后面能接不定式作賓語的動詞有：agree, ask, choose, decide, forget, hope, learn, want, wish, would like等。we hope to get there before dark. 我們希望天黑以前到那兒。the girl decided to do it herself. 那個姑娘決定自己做那件事。動詞不定式作賓語的注意事項（2點）1. 有些動詞既可跟不定式作賓語，也可跟動名詞作賓語，但含義不同：remember to do 記住要做某事remember doing 記得曾經(jīng)做過某事forget to do忘記要做某事forget doing 忘記曾經(jīng)做過某事stop to do 停下來去做某事stop doing 停止做某事go on to do 繼續(xù)做另一件事go on doing 繼續(xù)做原來在做的事i remember seeing you somewhere before.我記得以前在哪兒見過你。please remember to turn off the light when you leave.離開時請記得關(guān)好燈。2. 不定式作賓語時，如帶有賓語補足語，則要把不定式放到后面，用it作形式賓語，構(gòu)成“主語+動詞+it+賓補（形容詞、名詞）+不定式”結(jié)構(gòu)。如：he found it very difficult to get to sleep.他發(fā)現(xiàn)很難入睡。四. 動詞不定式作賓語補足語1. 后面能接to不定式作賓語補足語的動詞有：ask, order, teach, tell, want, wish, help等。the teacher told us to do exercise 1. 老師要我們做練習一。i want both of you to go. 我要你們倆去。we helped her (to) repair her bike. 我們幫助她修理自行車。2. 使役動詞let, have, make及感官動詞see, watch, notice, hear, feel等要以不帶to的不定式作賓補。lets have a rest. 我們休息一會吧。i saw him come in. 我看見他進來了。感官動詞后既可跟不帶to的不定式作賓補，也可跟v-ing作賓補，前者表示動作的全部過程已結(jié)束；后者表示動作正在進行。i saw him come downstairs.我看見他下了樓。（說明他下樓了這件事）i saw him coming downstairs.我看見他在下樓。（說明他下樓時的情景）五. 動詞不定式作狀語later he left home to work in different cities. 不久他離開家到不同的城市工作。he went to see a football match. 他去看足球比賽了。in order to catch the other students, i must work hard.為了趕上其他同學，我必須努力學習。六. 動詞不定式作定語不定式作定語一般放在所修飾的詞的后面。i need something to eat.do you have something to read?tom was so excited that he had no word to say.he is really a fool only to eat.the man to stand here just now is our english teacher.the doctor had no way to save the patient.注意：（1）作定語的不定式是由及物動詞組成，被修飾的名詞或代詞與不定式之間存在方位或方式關(guān)系需要有介詞。i am looking for a room to live in. 我正在找一間住房。（方位關(guān)系）we have many things to do experiments with.我們有許多做實驗的東西（方式關(guān)系）（2）作定語的不定式是由“be + adj + prep”構(gòu)成的動詞短語。here there isnt any book for me to be interested in.we have done many things to proud of. 我們做了許多引以自豪的事。七. 動詞不定式作主語to give is better than to receive.to reach there on foot is impossible.動詞不定式作主語時，可以用it 代替，把實際主語不定式放在后面。its better to give than to receive.its impossible to reach there on foot.its + adj + for sb. to do sth.its not difficult for me to study english well.its easy for him to work out this math problem.在這個句型中，如果形容詞與不定式的邏輯主語關(guān)系密切，并且形容詞用來說明邏輯主語的性質(zhì)、品質(zhì)、特點等，由of引出邏輯主語。這類形容詞主要有nice, kind, good, wrong, right等。八. 動詞不定式和疑問詞連用動詞不定式可以和疑問詞what, which, how, where, when連用，構(gòu)成不定式短語，可以作主語、賓語、表語、賓語補足語等。how to do is still a question.have you decided when to leave?九. 動詞不定式的否定形式動詞不定式的否定式是在to前加not；不帶to的不定式則在動詞前加not. 如：zhang ming asked me not to stay at home all day. 張明要我不要整天呆在家里。my mother let me not do it by myself. 媽媽讓我不要獨自做這件事。被動語態(tài)英語有兩種語態(tài)：主動語態(tài)和被動語態(tài)主動語態(tài)（the active voice）表示主語是動作的執(zhí)行者。被動語態(tài)（the passive voice）表示主語是動作的承受者。構(gòu)成：承受者+助動詞be+及物動詞的過去分詞+by+執(zhí)行者一般現(xiàn)在時：承受者+助動詞am / is/are +及物動詞的過去分詞+by+執(zhí)行者一般過去時：承受者+助動詞was / were +及物動詞的過去分詞+by+執(zhí)行者承受者+助動詞shall / will be+及物動詞的過去分詞+by+執(zhí)行者承受者+助動詞 have/ has been+及物動詞的過去分詞+by+執(zhí)行者承受者+ can /may/must/should +be+及物動詞的過去分詞+by+執(zhí)行者被動語態(tài)用法：1）當我們不知道動作的執(zhí)行者是誰，或者沒有必要指出動作的執(zhí)行者時，需用被動語態(tài)。2）當我們需要強調(diào)動作的承受者時,常用被動語態(tài)。3）如果需要說出動作的執(zhí)行者, 用by引導出動作的執(zhí)行者。主動語態(tài)變?yōu)楸粍诱Z態(tài)時，其謂語動詞的時態(tài)要與原句時態(tài)保持一致，其謂語動詞的數(shù)要與新主語保持一致。主動語態(tài)變?yōu)楸粍诱Z態(tài)時有以下幾種情況：1）主語謂語動詞賓語將主動語態(tài)的賓語變?yōu)楸粍诱Z態(tài)的主語。（主動）we bought a book yesterday.（被動）the book was bought yesterday.2）主語謂語動詞間接賓語直接賓語將主動語態(tài)中一個賓語變?yōu)楸粍诱Z態(tài)的主語。多數(shù)情況下將間接賓語變?yōu)橹髡Z。如果直接賓語變?yōu)橹髡Z時，間接賓語前要加介詞to / for。（主動）he showed me a book yesterday.（被動）i was showed a book yesterday.（被動）the book was showed to me yesterday.3）主語謂語動詞復合賓語含有一個由賓語加賓語補足語構(gòu)成的復合賓語，變?yōu)楸粍诱Z態(tài)時，將主動語態(tài)的賓語變?yōu)楸粍诱Z態(tài)的主語，賓語補足語保留不變，成為主語補足語。（主動）i found him a good pupil. （賓語補足語）（被動）he was found a good pupil. （主語補足語）4）短語動詞變?yōu)楸粍诱Z態(tài)有些短語動詞相當于一個及物動詞，其后可以接賓語，因此它們也有被動語態(tài)，但短語動詞是不可分割的整體，變?yōu)楸粍诱Z態(tài)時不可去掉其后面的介詞或副詞。（主動）we should look after the patients very well.（被動）the patients should be looked after very well by us.5）賓語從句變?yōu)楸粍诱Z態(tài)若主動語態(tài)中是賓語從句，變?yōu)楸粍诱Z態(tài)時常用it作形式主語，而把真正的主語放在后面。its said that he passed the exam.被動語態(tài)應(yīng)注意的幾個特殊問題：（1）不及物動詞帶介詞和介詞賓語，在變?yōu)楸粍诱Z態(tài)時，仍然要帶上介詞。（主動）the students in class listen to the teacher carefully.（被動）the teacher is listened to carefully by the students in class.（2）當動詞帶有復合賓語時，并且賓補是省去“to”的動詞不定式時，在被動語態(tài)中應(yīng)加上“to”。（