人教版八年级下册英语unit8 Section A 3ppt课件.ppt

1、Read the following sentences we have seen. Have you read Little Women yet? Yes, I have./ No, I havent. Has Tina read Treasure Island yet? Yes, she has. She thinks its fantastic. Have you decided which book to write about yet? Yes, I have. Ive already finished reading it. It was really good. 用法用法 1.

2、表示过去发生或已经完成的某一动作表示过去发生或已经完成的某一动作 对现在造成的影响或结果。对现在造成的影响或结果。 e.g. Have you had your lunch yet? Yes, I have. Ive just had it. (现在现在 我不饿了。我不饿了。) 2. 表示动作或状态从过去某一时刻开始，表示动作或状态从过去某一时刻开始， 一直延续到现在，而且可能还要继续一直延续到现在，而且可能还要继续 下去。下去。 e.g. I havent seen her these days. Ive known Bob for three years. Ive been at this

3、 school for over two years. 时间状语时间状语 already, yet, just, ever, never, before 构成构成 现在完成时是由“现在完成时是由“助动词助动词have / has+ 动动 词的过去分词词的过去分词”构成的，规则动词的过”构成的，规则动词的过 去分词构成与过去式相同，不规则动词去分词构成与过去式相同，不规则动词 的过去分词则需逐个记忆。的过去分词则需逐个记忆。 动词的过去式的变化和过去分词的动词的过去式的变化和过去分词的 变化并不完全相同。我们对它们作了一变化并不完全相同。我们对它们作了一 个大致的分类。个大致的分类。 (注：例子

4、中单词的变注：例子中单词的变 化顺序为：动词原形化顺序为：动词原形 动词的过去动词的过去 式式 动词的过去分词动词的过去分词) 一、过去式和过去分词的变化相同一、过去式和过去分词的变化相同 规则变化规则变化： 1. 一般在动词词尾直接加一般在动词词尾直接加ed。如：。如： pick picked picked; wish wished wished; stay stayed stayed 2. 以不发音的以不发音的e结尾的动词后面加结尾的动词后面加d。如：。如： like liked liked; hope hoped hoped; phone phoned phoned 3. 以“辅音字母以

5、“辅音字母 + y”结尾的动词，变结尾的动词，变y为为i， 再加再加-ed。如：。如： study studied studied; hurry hurried hurried; reply replied replied 4. 词尾只有一个辅音字母的重读闭音节动词尾只有一个辅音字母的重读闭音节动 词，要双写辅音字母，再加词，要双写辅音字母，再加-ed。如：。如： stop stopped stopped; clap clapped clapped 不规则变化：不规则变化： 5. 以不变应万变以不变应万变。如：。如： let let let; put put put; read read re

6、ad 6. 若中间有双写若中间有双写e，则去掉一个，则去掉一个e，单词，单词 末尾再加末尾再加t。如：。如： feel felt felt; keep kept kept; sleep slept slept 7. 结尾的字母结尾的字母d变变t。如：。如： lend lent lent; build built built; send sent sent 8. 变为以变为以-ought或或-aught结尾结尾。如：。如： buy bought bought; bring brought brought; catch caught caught; teach taught taught 句式句式

7、 1. 肯定句：主语肯定句：主语 + have / has + 过去分词过去分词 (+ 其他其他) 2. 否定句：主语否定句：主语 + have / has + not + 过去过去 分词分词(+ 其他其他) 3. 一般疑问句：一般疑问句：have/ has + 主语主语 + 过去过去 分词分词(+ 其他其他) 4. 特殊疑问句特殊疑问句： 1) 特殊疑问词特殊疑问词 (不是句子主语不是句子主语) + have / has + 主语主语+过去分词过去分词 (+ 其他其他) 2) 特殊疑问词特殊疑问词(是句子主语是句子主语)+have / has+ 过去分词过去分词(+ 其他其他) alread

8、y和和yet都可以作为现在完成时的标都可以作为现在完成时的标 志词，但它们的用法不同。志词，但它们的用法不同。 already一般用于肯定句中一般用于肯定句中。如：。如： We have already cleaned up our classroom. 注意：注意：already用于疑问句中时通常表用于疑问句中时通常表 示惊奇示惊奇。如：。如： Have you finished your homework already? I cant believe it. yet一般用于疑问句和否定句中一般用于疑问句和否定句中。如：。如： Have you seen her yet? The bus

9、hasnt come yet. 1. Write the forms of the past tense and past participle: drink _ _ see _ _ find _ _ leave _ _ tell _ _ drank drunk saw seen found found left left told told Why is Mr. Yang still in the teachers office? Maybe he _ his work yet. A. doesnt finish B. hasnt finished C. havent finished B

10、4a Use the words in brackets to complete the conversations. 1. A: Would you like something to drink? B: No, thanks. _. (just/ drink some tea) 2. A: I heard you lost your key. _? (find) B: No, not yet. I have just drunk some tea Have you found it 3. A: Do you know when Tom is leaving? B: _. (already/

11、 leave) A: When _? (leave) B: This morning. 4. A: Is your sister going to the movies with us tonight? B: No. _. (already/ see the film) He has already left did he leave She has already seen the film 5. A: What do your parents think about our plan? B: I _. (not/ tell them/yet) havent told them yet 4b

12、 Fill in the blanks with the correct forms of the words in the brackets. Sally _ (love) reading. In the morning she reads the newspaper and in the evening she reads books. She _ already _ (read) more than 100 different books. Her favorite kind of books is science fiction. She is interested in scienc

13、e and technology and loves to imagine what the world _ (be) like in 50 years. loves has read will be She _ (finish) reading a book about robots last week and _ (write) a book report about it next week for her French class. Every time she is in the library, Sally looks at the many books she _ (not re

14、ad) yet and she cant wait to read them. finished will write hasnt read 4c Complete the chart with information about you and your friend. A: What books have you already read? B: I have already read Tom Sawyer and Harry Potter. A: What do you think of them? B: Well, I think Harry Potter was exciting,

15、but Tom Sawyer was a bit boring. You Your friend Comments Books I have already read Movies I have already seen Songs I have already heard ( )【2013广西贵港广西贵港】 Do you know the movie Lost in Thailand? Yes. I _ it twice. Its funny. A. saw B. see C. have seen D. will see C ( )【2013黑龙江牡丹江黑龙江牡丹江】 Lunch? No, thanks. I_. A. will eat B. am eating C. have eaten ( )【2013 湖北黄冈湖北黄冈】 Where is Tom? We cant find him anywhere. Perhaps he _ home. A. has come B. is going C. went D. was going C A Retell what you did yesterday and what you have done now.