Unit10 SectionA 现在完成时态专项讲解 课件2020-2021学年人教版英语八年级下册

现在完成时 (1). 句型结构：have / has + done He has already finished his homework. →He hasn’t finished his homework yet. (否定句，在has, have后+not) →Has he finished his homework yet? (一般疑问句，将has, have提到句首) →Yes, he has. / No, he hasn’t. (回答) (2). 用法：1).过去发生的动作对现在造成的影响。 I have closed the door. (门现在是关的) 2).过去已经开始，持续到现在的动作或状态。 We have lived here for two years. (从过去住到现在) 3).表示开始于过去并持续到现在的动作或状态。（动词 多为延续性动词） 时间状语：表示从过去某一时刻延续到现在的一段时间的状语, 常由for/since引导（for+时间段，since+时间点）。 eg. for an hour, for two weeks, for ten years, since 2000, since last week/month/year/…, since three days ago, since he came here We have stayed here for two weeks. Mr. Green has lived in China since 2000. Since 后的从句时要用一般过去式 We have done several things since we came back. 用since或for填空： 1.I have been at this school_______ more than two months. 2.She has worked in the factory_____ two years ago. 3.Mr Green has lived in the city______ he was born. 4.His father has been a Party member______ twenty years. 5.They have visited many countries_______ 2000. 6.We have worked there _______ a long time. 7.How many books have you read ____ last month. 8.They have done something useful to improve the environment_______ they came to Sanming. 9.What have you done ____ you became a student? for since since for since for since since since 常用短暂性动词和延续性动词 buy—have borrow—keep become/get—be finish—be over die—be dead leave—be away from come/go back—be back begin --- be on join—be a member of /be in… eg.1) The river has become dirty. The river has been dirty for a long time. 2) My father has left Sanming. My father has been away from Sanming since last month. 3) The TV play has begun. The TV play has been on since two hours ago. 1.The scientist ____from home for three months. A. has left away B. left away C. has been away 2.Mr Brown __