八年级下册语法专题一：情态动词should与could知识讲解

八年级下册语法专题一：情态动词s h o u l d
与c o u l d
专题归类复习一
情态动词should与could的用法
●语法讲解
1．should是情态动词shall的过去式，但有时并不表示过去。

(1)表示委婉的劝告或建议，意为“应该”。

如：
You should hand in your composition at once.
你应该立刻交上你的作文。

(2)表示可能性或推断，意为“可能；应该”。

如：
I think they should be there now.
我想他们现在应该在那里。

(3)用于特殊疑问句中，表示意外、惊奇、不能理解等强烈感情。

如：How should you know that?
你是怎么知道那件事的？
What should you do to relax?
你该做什么来放松呢？
2．could是情态动词can的过去式，但有时并不表示过去。

(1)表示提议，比can更客气、委婉。

I could do the shopping for you, if you are tired.
如果你累了，我能帮你买东西。

(2)表示请求，语气比can更客气、委婉。

Could you show me the way to the hospital?
你能告诉我去医院的路吗？
●语法精练
Ⅰ.单项选择
( )1.Schools________allow students at least one hour
a day for sports.
A．would B．might
C．should D．could
( )2.________you tell me how to get to the post
office?
A．Must B．Need
C．Could D．Should
( )3.—When can I come for the photos? I need them
tomorrow afternoon.
—They________be ready by 12：00.
A．can B．should
C．might D．need
( )4.—Could I borrow your dictionary?
—Of course you________．
A．can B．must
C．should D．will
( )5.The basketball________his.He loves playing
basketball.
A．maybe B．may be
C．may is D．may not
( )6.We________keep the new traffic law and learn how to protect ourselves.
A．will B．would
C．shall D．should
( )7.—Could you please help me do my homework?
—Sorry.I________．You________do it by yourself.
A．could; may
B．couldn't; should
C．can't; should
D．can't; may
( )8.—How was the youth club last night, Mark?
—It was great fun.You________come.
A．must B．can
C．should D．may
Ⅱ.根据句意用should或could填空
1．Sally________make dumplings by herself when she was only five years old.
2．In school, all the classmates__________get on well
with each other.
3．You________call her if you have something important to tell her.
4．You_________not drive after drinking.
5．_________I use your mobile phone，please?。