现在完成时的简介.doc

1、 现在完成时的简介一、概念：表示过去发生或已经完成的动作对现在造成的影响或结果，也可表示从过去一直延续到现在的动作或状态二、结构：（一）肯定句 主语＋have ／has ＋过去分词＋其它1）I've copied all the new words ．我已经抄写了所有的生词 (表示不要再抄了)2）She has lost her books ．她丢失了她的书 （表示到目前为止还没有找到）(如果用过去时：She lost her books . 则强调书是过去丢的这一动作，而不知现在有没有找到)3）We've just cleaned the classroom ．我们刚好打扫了教室表明现在教室是干净的）（二）否定句 主语＋have ／has＋not＋过去分词＋其它 1）I haven't finished my homework yet．我还没有完成我的作业 2）She hasn't travelled on a train ．她没有坐火车旅行过 3）We have never spoken to a foreigner．我们从来没有和外国人说过话 注：有时not可以用never代替，表示“从来没有”的意思。

又如： 4）I have never seen him before．以前我从来没有见过他三）一般疑问句 Have ／Has ＋主语＋过去分词＋其它 ？回答： Yes, 主语 + have / has.(肯定)No, 主语 + haven’t / hasn’t.(否定)1）—Have you ever made dumplings ？你曾经做过饺子吗？ 　 —Yes ，I have ．是的，我做过 2）—Has she ever danced before ？她曾经跳过舞吗？ —No，never．不，从来没有 3）—Have they found the lost books yet ？他们已经找到了丢失的书吗？ —Yes ，they have．是的，他们找到了三：动词的过去分词 ----一般情况加ed（不规则变化见P126—P129表格）常考的不规则动词过去分词：be—was/were—been do—did—doneeat—ate—eatengo—went—gonesee—saw—seenfind—found—foundhave/has—had—hadmake—made—madelet—let—letput—put—put A) 选用have, has填空：1. I _______ told him the news.2. She _______ come back from school.3. You _______ won the game.B) 按要求改写下列各句：4. They have bought a computer. (改成否定句) _________________________________________5. He has lost his book. (先改成一般疑问句，再作肯定与否定回答) — ______________________ — ______________________四：四大标志词1、以already, just和yet为标志already, just和yet表示到现在为止动作或状态已经、刚刚或还没有发生。

yet通常在否定句） He has already got her help.　他已得到她的帮助 He has just seen the film.　他刚刚看过这场电影He hasn’t come back yet.　他还没有回来 2、以ever和never为标志ever和never表示到现在为止动作或状态曾经或从来没有发生过This is the best film I have ever seen.　这是我曾经看过的最好的一部电影He has never been to Beijing.　他从没有到过北京3、以动作发生的次数为标志　　若某一动作到现在为止已经发生了若干次，则要使用现在完成时He has been to the USA three times.他已经去过美国三次了4、以so far为标志　　so far往往表示到目前为止动作或状态已经发生He has got to Beijing so far.　到目前为止他已到了北京She has passed the exam so far.　到目前为止她已经通过了考试五：持续性用法表示从过去持续到现在的动作或状态此时常与“for ＋时间段”或“since＋时间点”He has been away for two years.　他已走了两年。

for +时间段)He has been an English teacher since 1992.　自从1992年以来他一直当英语教师 (since +过去某一时刻)He has taught in our school for 30 years.He has taught in our school since 1976.I have been in China for 10 years. I have been in China since 2000.。