想要学好英语四级怎么能不知道情态动词的用法呢?下面就让小编为大家详解一下吧。
情态动词属于非实意动词,它虽具有一定的词义,但这种词义并不完整,语法上也不能单独构成谓语,它必须和另一个实
情态动词属于非实意动词,它虽具有一定的词义,但这种词义并不完整,语法上也不能单独构成谓语,它必须和另一个实意动词一起构成谓语才能表达完整的意思。情态动词是一类非常活跃的非实意动词,归纳起来,情态动词在句子中主要有三种用法:
1.情态动词的非推测性用法
其用法是用来表示能力、许可、必要、义务、命令、劝告、询问、需要、应该、敢于等概念或态度,这类情态动词有:can(could),may(might),shall(should),will(would),must,
oughtto,need,dare等,例如:
Children,you can eat something you like.
Everybody must pay the fare,but you need not do so right away.
How dare you come out without your parents’permission?
I would rather stay at home than go with you.
Ought not parents to give their child more care?
You are not so young;you should not do such silly things any more.
疑问句中的情态动词和答语中的情态动词有固定的搭配形式。例如:
-Could I borrow your bike for a while?
-Yes,you can.(-Yes,please.)
-No,you can not.
-May I discuss something on practicing spoken English with you now?
-Yes,you may.(-Yes,of course.)
-No,you mustn’t.
-Need everyone fill in this application form immediately?
-Yes,everyone must.(Yes,everyone do.)
-No,they needn’t.
-Must we hand out emergency rations to these famine refugees this instant?
-Yes,you must.
-No,you they needn’t.
-No,you don’t have to.
2.情态动词的推测性用法
人们常常会对客观事物做出自己的判断,当情态动词用来表示说话人对事物的推测、判断时,就具有情态动词的.推测性用法。可以用作推测的情态动词有can,could,may,might,must,ought to, should,will和would。它们做出可能性的推测、判断、预料的程度是不同的,might最弱、最没有把握,而must最强、把握最大。例如:
It’s nine o’ friend couldn’t come to see me.
This boy must fail in exam from his sad face.
It’s five past e ought to be many students waiting for the door opening.
She should be a clerk in foreign company according to her formal dress.
He may not be fine in these days.
They were ready for a strong earthquake which might occur.
有时,情态动词用不同的动词时态来推测表达对不同时间的事物的推测,例如:
My friend may be still sleeping at home now.(对现在说话时正在发生的事物的推测)
Can we be working at the same company next year?(对将来的推测)
His clothes is must have forgotten to bring the umbrella.(对已经完成的情况的推测)
3.情态动词用于虚拟语气
A:提出一个假设的条件,纯粹的展望或提出命令、要求。有部分情态动词的过去时态常用于这种用法。
例如:Wish I might be better soon.
Should my friend come,ask him to wait in the reading-room.
May you be healthy forever.
If you dared to say such words to me,I would give up making friends with you.
B:比较委婉地陈述看法,提出要求和建议,谓语动词通常是情态动词的过去时态。例如:
It would not be useful to adopt such suggestion.
Could you leave the message with me?
C:情态动词加动词的完成时态用来表示对过去情形的虚拟,这种设想或看法同过去的事实是相反 的,表示"本应该做",而实际上没做。例如:
We ought to have been here early.
This is something you shouldn’t have done.
Need you have nosed about in her affair?It was none of your business.