英语人教版八年级下册初中英语现在完成时的讲解.docx

现在完成时Teaching aims:1.学生了解动词的过去式和过去分词。2.学生掌握理解现在完成时态的用法。3.学生基本会用现在完成时。Teaching important and difficult points:1. 现在分词的变化形式。2. 现在完成时for与since的用法区别。3.瞬间动词转换成延续性动词。Teaching procedures:Step1.现在完成时的构成:肯定句：have/has +done 否定句：have/has +not+done 一般疑问句：Have/Has+主语+done?Step 2.现在完成时的主要用法:用法一：表示过去发生的某一动作对现在造成的影响或结果.I have already read this book. 我已经读过这本书了。（知道书中的内容）I have washed my clothes already . 我已经洗了衣服。（衣服洗干净了）I have just finished my homework. 我刚做完我的家庭作业。（作业没有了）用法二：表示过去某个时间开始的动作一直持续到现在并且还有可能持续下去。for+时间段 since+时间点/句子I have learnt English for more than ten years.我已经学了10多年的英语。(从10年前开始,持续到现在还在学)She has swum since half an hour ago.她已经游泳了半个小时。(半个小时前已经开始游泳,到现在还在游)Step3.现在完成时的时间状语:现在完成时常与副词already, yet, never ,just， ever 等连用。1. already 意为“已经”，通常用于肯定句，可放在助动词之后，过去分词之前，也可放在句末。2. yet 在疑问句中意为“已经”，在否定句中意为“还（没）”，放在句末。3. never 意为“从来没有”常与before连用，多放在助动词与过去分词之间。4. Just 意为“刚刚”，表示行为刚刚过去，常放在助动词与过去分词之间。5. ever 意为 “曾经”，用于疑问和否定句中，常放在助动词与过去分词之间。for+时间段 since+时间点/从句so far “到目前为止”Step 4.短暂性动词与时间段的关系:leave-be away (from) come/go (to) -be (in/at)arrive (at/in)- be (in/at) get (to)-be (in/at)reach-be (in/at) buy-haveborrow-keep finish-be overjoin-be in start/begin-be ondie-be dead close-be closedopen-be open return-be backmarry-be married become-beStep5.have been 与have gone 比较:have been to 意思是“到过，去过”，表示曾经到过某处，但现在人不在那儿。have gone to 意思是“去了”，表示已经去了某地，现在人可能在去的途中或已在那儿了。have been in 意思是“呆在某处一段时间了”练习题1. 用 for和 since填空:_ a long time. _since5oclock._ 2017. _fivehoursago._ 20 minutes. _two weeks._ he came to China. _ last month. _ several years. _ three days ago.2.用正确的形式填空：1. I _(have) lunch already.2. Has the train_ (arrive), yet?3.Tome _ never_ (be to ) China.4. The twin _just _(see) my father.5. The twins _(see) my father just now.3.用所给单词的正确形式填空：1._ you _(clean) the room? Yes, we _(do) that already. When _ you _(do) it? We _(do) it an hour ago.2._ he _(see) this film yet? Yes. When _ he _(see) it? He _ it last week. 3. How many times _you_(be) there? 4. I _ (read) the novel twice. Its interesting.5. She _(go) to Pairs, hasnt she? Yes. How _ she _(go) there? She _(go) there by air.6. So far, many countries _(develop) their software programs.7.Mr Chen _(give)up smoking last year.8.Mr Chen _(give) up smoking since last year.4.完成句子：1. 你曾经吃过鱼和薯条吗？_you ever _ fish and french frise?2. 我刚刚丢了我的语文书。I _ just _my Chinese book.3. 我以前从来没去过那个公园。I _ _ _ _ that park.4. 他已经吃过午饭了。He _ _ _lunch.5. 你已经看过这部电影了吗？_ you _ this movie _?5.找出错误并改正：1.I have got to Paris for one week . 2. My brother has joined the army for five years. 3. I have left Shanghai for 3 days. 4. I have borrowed the dictionary since 3 days ago . 5. The film has b