語法復(fù)習(xí)二十：介 詞
介詞又叫前置詞，是一種虛詞。介詞分為三種，一種是簡單介詞，如at, in, on, beside, to , for等；另一種是短語介詞，即由兩個以上的詞組組成的短語，如in front of, because of, out of, instead of等；還有一種叫二重介詞，如until after, from behind等。�。ㄒ唬┙樵~的句法功能
介詞不能獨立在句中做成份，介詞后必須與名詞、代詞、或動名詞構(gòu)成介詞短語在句中充當(dāng)一個成份，表示人、物、事件等與其它人、物、事件等之間的關(guān)系。
1、作定語：The book on the table is mine.
2、作狀語：We have breakfast at seven.（表時間）；They were late for meeting because of the heavy rain.（表原因）；They started the machine by pressing the button.（表方法）
3、作表語：My dictionary is in the bag.
4、作賓語補足語：I found him in the office.
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1、表示時間的at, in, on：at表示片刻的時間，如：at 8 o'clock ，常用詞組有：at noon, at night, at midnight, at the end of, at that time, at the beginning of, at the age of, at Christmas, at New Year等。in表示一段的時間，如：in the morning, in the afternoon, in the evening, in October, in 1998, in summer, in the past, in the future等。on總是跟日子有關(guān)，on Monday, on Christmas morning, on the following, on May Day, on a warm morning等。
2、表示時間的since和from：since表示從過去到現(xiàn)在的一段時間的過程，常與現(xiàn)在完成時連用。from表示從時間的某一點開始，不涉及與現(xiàn)在的關(guān)系。一般多與現(xiàn)在時、過去時、將來時連用。如：I hope to do morning exercises from today./ We have not seen each other since 1995.
3、表示時間的in和after：兩者都表示"在（某個時間）之后，區(qū)別在于in表示"在（一段時間）之后"，而after則表示"在（某一具體時間點之后）"，in短語和將來時態(tài)連用，after短語和過去時態(tài)或?qū)頃r態(tài)連用。如：We'll be back in three days./ After seven the rain began to fall./ What shall we do after graduation?
注意：after有時也可以表示在一段時間之后（常用在過去時里）。如：After two months he returned.
4、表示地理位置的in, on, to：in表示在某范圍內(nèi)，on指與什么毗鄰，to指在某環(huán)境范圍之外。如：Changchun is in the northeast of China./ Mongolia is on the north of China./ Japan is to the east of China.
5、表示"在……上"的on和in：on只表示在某物的表面上，而用in表示占去某物一部分。 如：There is a book on the piece of paper./ There is an interesting article in the newspaper./ He dug a hole in the wall.
6、表示"穿過……"的through和across：through表示從內(nèi)部通過，與in 有關(guān)；across則表示從一端至另一端在表面上的通過，與on有關(guān)。如： Water flows through the pipe./ The old man walked across the street.
7、in the corner, on the corner, at the corner：in the corner 表示在角落里，in指角的內(nèi)面；on the corner表示"在角上"，on指的不是內(nèi)面，也不是外面，而含內(nèi)外兼有之意；at the corner指"在拐角處"，at指的是拐角外附近的外面。如：The lamp stands in the corner of the room./ I met with him at the street corner./ He sat on the corner of the table.
8、in the end, at the end of, by the end of：in the end作"最后"、"終于"解，可單獨使用，后不接介詞of；at the end of 表示"在……末梢"，"到……盡頭"，既可指時間，也可以指地上或物體。不可單獨使用；by the end of 作"在……結(jié)束時"，"到……末為止"解，只能指時間。不可單獨使用。如：In the end they reached a place of safety./ At the end of the road stands a beautiful garden./ They decided to have an English evening at the end of this week./ by the end of last month he had finished the novel.
9、表示"關(guān)于"的about 和on：兩者都有"關(guān)于"的意思，不過前者為一般用詞，而后者為較正式的"論述"。如：He came to tell me about something important./ He wrote a book on science.
10、between, among：一般說來，between表示兩者之間，among用于三者或三者以上的中間。如：You are to sit between your father and me./ He is always happy among his classmates.
注意：但有時說的雖然是三個以上的人或東西，如果強調(diào)的是兩兩相互間接關(guān)系，適用于between。如：Agreements were made between the different countries. 在談到一些事物或一組事物，而把它們視為分居兩邊時用between。如：The little valley lies between high mountains.。在談事物間的差別時，總是用between。如：They don't know the difference between wheat, oats and barley.
11、besides, except, but, except for：besides指"除了……還有，再加上"。如：All went out besides me.；except指"除了，減去什么"，不能放在句首。如：All went out except me.；but 與except意思近似，表示"除了……外"經(jīng)常用在no, all, nobody, anywhere, everything等和其他疑問詞后面。如：I never saw him reading anything but the newspaper.；except for表示"如無……就，只是"表明理由細節(jié)。如：His diary is good except for a few spelling mistakes.。
12、表示"用"的in和with：表示工具的"用"，用with，而表示材料、方式、方法、度量、單位、語言、聲音等的"用"，用in。如：He is writing a letter with a pen./ He wrote the letter in pencil./ We measured it in pounds./ Read the text in a loud voice./ Tell me the story in English.
13、in charge of和in the charge of：兩者都表示"由誰負責(zé)、照顧、管理"。區(qū)別在于：in charge of后接被照管的人或物，而in the charge of后面則跟照管的人。如：Who is in charge of the project?/ The project is in the charge of an engineer.。
14、as, like：as作"作為"、"以……地位或身份"解。如：Let me speak to you as a father.（事實是父親）；like作"象……一樣"解。如：Let me speak to you like a father.（事實上不是父親）。
15、in front of 和in the front of：in front of = before，是"在……前面"的意思（不在某物內(nèi)）； in the front of則是"在……前部"的意思（在某物內(nèi)）。如：There is a desk in front of the blackboard./ The boy sat in the front of the car.。
16、in, into：into表示動向，不表示目的地或位置。如：We walked into the park.；in通常表示位置。如：We walked in the park；in和drop, fall, put, throw, break等終止性動詞連用時，也可以表示動向。如：I have put the coin in (into) my pocket.我把硬幣放進衣袋。
練習(xí)（一）、介 詞
1. The teacher is writing ____ a piece of chalk on the blackboard while the students are writing ____ink in exercise books. A. with, in B. in, with C. in, in D. with, with
2. The worker can make chairs ____ wood, and also can make paper ____ wood.
A. from, of B. of, from C. of. of D. from, from
3. Mary dropped in ____ Mr Smith, but he wasn' t at home, so she went to drop in ____ Mr Smith's office. A. on, on B. at, at C. on. at D. at. on
4. The teacher is not only strict ____ his pupils but also strict ____ his own work.
A. with, with B.in,in C. in, with D. with, in
5. His grandfather died ____ the wound that the enemy soldier had given him .and then his grand-
mother died ____ hungry and cold. A.from,of B.of,from C.from,from D.of.of
6. If you run ____ two hares you will catch neither. A.into B.after C.off D. out of
7. This is a common mistake ____ students. A. between B.over C. among D. about
8. My father began to work ____ a bus driver when he was twenty years old.
A.for B.to C.at D.as
9. _____ hearing the n