内容正文:
八年级下册Unit 7 A Good Read单元语法讲解
现在完成时(讲解一)
一、现在完成时的概念
1、现在完成时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,
例如:I am not thirsty now because I have drunk some water.
2、 或表示从过去某一时间开始并一直持续到现在的动作或状态。
例如:He has done his homework for two hours.
二、现在完成时的基本结构
1、肯定句:主语+have/has+动词的过去分词(+其他)
例如:These people have waited for the star for two hours.
这些人已经等这个明星两个小时了。
2、否定句:主语+have/has+not+动词的过去分词(+其他)
例如:We have not seen him for long. 我们很久没见到他了。
3、一般疑问句及其简略回答
Have/Has+主语+动词的过去分词(+其他)?
肯定回答:Yes,主语+have/has.
否定回答:No,主语+haven’t/hasn’t.
例如:—Has she arrived in Nanjing? 她已经到南京了吗?
—Yes, she has. /No, she hasn’t. 是的,她已经到了。/不,她还没到。
4、特殊疑问句
疑问词(组)+have/has+主语+动词的过去分词(+其他)?
How long have you studied Chinese? 你学语文多长时间了?
三、现在完成时标志词
1、already、yet和just
当表示动作已经完成并对现在有一定影响时,我们一般用现在完成时。同时,可分别用yet、already或just加以强调或说明。
already意为“已经”,通常用于现在完成时的肯定句中。
例如:They have already told me that. 他们已经告诉我那件事了。
yet常用于现在完成时的否定句或疑问句中,谈论尚未发生但可能发生的事。
例如Have you finished your housework yet? 你做完家务活了吗?
just意为“刚刚”,表示动作刚刚结束,常放在助动词与过去分词之间。
例如:What you’ve just told me is very amazing. 你刚刚告诉我的事很令人惊讶。
四、现在完成时的两个特殊句型
1、have ever done 曾经做过某事 (ever意为“曾经”,常用于疑问句或否定句中。)
例如: Have you ever been to Beijing? 你去过北京吗?
2、have never done 从来没做过某事 (never意为意为“从未”,表示否定含义。)
例如:He has never seen it.他从来没见过它。
五、现在完成时和一般过去时的区别
1、现在完成时:表示到说话时为止已经发生或完成(不一定结束)的动作或状态,强调造成的结果或对现在产生的影响。标志词:already、yet、just、never、recently、so far、for five days、since last year等。
例如:My father has been a teacher for five years. 我爸爸已经当老师五年了。
2、一般过去时:表示过去某个时间发生的事情或存在的状态,侧重陈述过去发生的事情或状态。标志词: yesterday、the day before yesterday、last week (night、month、year)、in 2020、two years ago等。
例如:My sister was a doctor five years ago. 我姐姐五年前是医生。
现在完成时(讲解一)专项练习
【基础练习】
一、单项选择
1.— Have you ________ the difficulty yet?
— No, I need more time.
A.solve B.solved C.solving D.solves
2.They ________ in this small town for 10 years. They enjoy staying here.
A.have lived B.lived C.will live D.live
3.—Has anyone ________ been to the moon?
—No, not ________. Maybe in the future.
A.already; yet B.ever; yet C.yet; ever D.ever; already
4.He ________ to Kunming three times, so he knows the city very well.
A.has gone B.has been C.went D.goes
5.How long ________ your mother worked as a teacher?
A.has B.have C.did D.does
6.He ________ that TV show.
A.seen B.has already seen C.have already seen D.already see
7.He ________ his study desk yet, so it’s very untidy.
A.hasn’t cleaned B.didn’t clean C.won’t clean D.doesn’t clean
8.I ______ just ______ my evening exercise, so I can play outside now.
A.have; finished B.did; finish C.will; finish D.had; finished
9.—What’s the matter, Lucy? Why are you upset?
—Mum, Linda ________ my sweets. There’s none left.
A.eats up B.eating up C.was eating up D.has eaten up
10.He ________ his travel notes yet, so he is still writing them.
A.hasn’t finished B.didn’t finish C.won’t finish D.doesn’t finish
参考答案
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