内容正文:
Unit 3
Language in use
Unit 3
Language in use
Have a try
好几亿年
绕……转
……当中没有一个
几个其他行星
太阳系
银河系
在宇宙中
在太空中
拍照
与……交流
在地球上
hundreds of millions of years
go around
none of
several other planets
solar system
the Galaxy/ the Milky Way
in the universe
communicate with
take photos
in space
on the earth
Present perfect (2)
Focus on
用法
1. just,already和yet在现在完成时中的用法;
2. 现在完成时与一般过去时的区别。
1. I have just heard the news.
2. Astronauts have already been to the moon.
3. We have just started to explore other planets.
两者都用于肯定句中,一般置于have/has之后, V-ed 之前
just 刚刚
already 已经
现在完成时与 just 和 already
我刚听到消息。
宇航员已经去过月球了。
我们才刚刚开始探索其他行星。
1. The scientists have not heard from it yet.
2. Man has not discovered any life in space yet.
3. Have the children come home yet?
yet置于句末
yet
用于
否定句:表示“还未(以后可能会)”
疑问句:表示“已经”
现在完成时与 yet
在现在完成时中,可分别用just, already 或yet 加以强调或说明。
科学家还没有收到它发出的信息。
人类尚未在太空中发现任何生命。
孩子们已经回家了吗?
现在完成时(just,already,yet)的用法
副词 用法
already 意为“已经”,常用在______句中。一般放在助动词have之后,过去分词之前
肯定
yet 意思为“还”,常用在______句或______句中,位于句尾
just 意为“刚刚”,常用在助动词have之后,过去分词之前
否定
疑问
一、单项选择
( ) 1. —Sally,I ______ the picture already.
—Wow,truly beautiful!
A. finish B. have finished C. was finishing
B
( ) 2. Meimei has ________ called me to tell that she couldn't come.
A. just B. yet C. today
( ) 3. He promised to pick me up at the school gate. However,he ________ yet.
A. didn't arrive B. hasn't arrived C. isn't arriving
A
B
现在完成时:
① She has already cleaned the floor.
② She cleaned the floor yesterday.
现在完成时与一般过去时
一、构成不同
她已经打扫了地板。
她昨天打扫了地板。
一般过去时:
主语 + have/has + been/V-ed
主语 + 动词过去式
现在完成时
副词作标志词:just, already, yet
since + 时间点/(时间段+ago)/一般过去时句子;for + 时间段
表示次数的时间状语:once, twice, three times, ever, never
一般过去时
过去时间点:just now, at that time, yesterday, this morning, three years ago等
过去时间段:in the past, in + 过去的年份, last week, once upon a time等
“最近”:lately,recently
“迄今为止”:so far, till now, up to now
三、时间状语不同
Simple past tense
Present perfect tense
构成
时间状语
语义侧重点
一般过去式
have/has