1.表過去發(fā)生的事情或存在的狀態(tài) egSuddenly,the clouds cleared and the rain stopped. 2.表過去經(jīng)常發(fā)生的事情 egI was very thin in my childhood. 3.帶有確定的過去的時間狀語 egDid you meet yesterday? He left just now.
1.表經(jīng)常發(fā)生的事情、存在的動作或狀態(tài) egShe sings with the band Crazy Boy. 2.表內(nèi)心活動感情等 egI don't think you are right. 3.描述客觀真理 egBirds fly in the sky. 4.表預定的行為 egThe train leaves at 9.
1.要在將來的某個時間內(nèi)發(fā)生，是“純粹的將來動作”。 egI shall / will not be free tomorrow. 2.表說話人的意圖、打算或某種可能性 egWho is going to speak first? 3.按計劃要發(fā)生的動作或命令他人做某事 egThe new bridge is to open to traffic in 3 days.
1.表示在過去某時刻正在進行的動作 egAt this moment yesterday, I was packing for camp. 2.用于故事的開頭，交代故事發(fā)生的背景情況 eg One night, he was typing in his study . Suddenly , a man broke … 3.表示在過去的未來時間要發(fā)生的動作 egWe left there when it's getting dark.
1.說話、寫文章的當刻正在發(fā)生的動作 egThey are having a football match. 2.現(xiàn)階段一直在進行的動作 egHe is preparing for CET Band Six. 3.表示說話人的情感，如贊許、批評等 egShe is often doing well at school. 4.表示在近期按計劃或安排要發(fā)生的動作 egAre you staying here till next week?
1.發(fā)生在“過去的過去” egWhen I woke up, it had stopped raining. 2.與一個表示過去的時間狀語連用 egPeter had collected more than 300 Chinese stamps by the time he was ten. 3.在過去某時之前開始一直延續(xù)到這一時間 eg By the end of last year, he had worked in the factory for twenty years.
1.賓語從句或間接引語中 egHe didn't expect that we would all be there. 2.表示過去習慣性的動作 egDuring that period, he would do this every day. 3.表示過去的愿望、傾向，多用于否定句 egThey knew that we would never permit such a thing.
1.表示截止現(xiàn)在業(yè)已完成的動作 egBy now, I have collected all the data that I need. 2.表示發(fā)生在過去而對現(xiàn)在產(chǎn)生影響、帶來結(jié)果的動作 egShe has been to the United States. 3.表示過去發(fā)生的動作持續(xù)到現(xiàn)在，并可能還要延續(xù) egI have learned English for 8 years.
