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英语中的情态动词是什么?

来源:学生作业帮 编辑:作业帮 分类:英语作业 时间:2024/05/04 12:29:31
英语中的情态动词是什么?
如题
情态动词是一种本身有一定的词义,表示说话人的情绪,态度或语气的动词,但不能单独作谓语,只能和其他动词原形构成谓语.
编辑本段分类:
情态动词有四类:
①只做情态动词:must,can(could),may(might),ought to
②可做情态动词又可做实义动词:need,dare
③可做情态动词又可做助动词:shall(should),will(would)
④具有情态动词特征:have(had) to,used to
编辑本段位置:
情态动词在句中放在谓语动词之前,谓语动词前若有助动词,则在助动词之前,疑问句中,情态动词则在主语之前.
I can see you.Come here.
我能看见你,过来吧.
He must have been away.
他一定走了.
What can I do for you?
你要什么?
How dare you treat us like that!
你怎能那样对待我们!
编辑本段特点:
情态动词无人称和数的变化,情态动词后面跟的动词需用原形,否定式构成是在情态动词后面加 "not".个别情态动词有现在式和过去式两种形式,过去式用来表达更加客气,委婉的语气,时态性不强,可用于过去,现在或将来.情态动词属非及物动词,故没有被动语态.
He could be here soon.
他很快就来.
We can't carry the heavy box.
我们搬不动那箱子.
I'm sorry I can't help you.
对不起,我帮不上你.
基本助动词与情态助动词最主要的区别之一是,基本助动词本身没有词义,而情态助动词则有自己的词义,能表示说话人对有关动作或状态的看法,或表示主观设想:
What have you been doing since?(构成完成进行体,本身无词义)
I am afraid I must be going.(一定要)
You may have read some account of the matter.(或许已经)
除此之外,情态助动词还有如下词法和句法特征:
1) 除ought和used以外,其他情态动词后面只能接不带to的不定式.如果我们把ought to和used to看做是固定词组的话,那么,所有情态动词无一例外地只能接不带to的不定式:
We used to grow beautiful roses.
I asked if he would come and repair my television set.
2) 情态助动词在限定动词词组总是位居第一:
They need not have been punished so severely.
3) 情态助动词用于第三人称单数现在时的时候,没有词形变化,即其词尾无-s形式:
She dare not say what she thinks.
4) 情态动词没有非限定形式,即没有不定式和分词形式,也没有相应的动名词:
Still,she needn't have run away.
5) 情态助动词的“时”的形式并不是时间区别的主要标志.在不少场合,情态助动词的现在时和过去时形式都可以表示现在、过去或将来时间:
Would you mind very much if I ask you to do something?
She told him he ought not to have done it.
6) 情态助动词之间是相互排斥的,即在一个限定动词词组中只能出现一个情态助动词,但有时却可以与have和be基本助动词连用:
You should have washed the wound.
Well,you shouldn't be reading a novel.
编辑本段用法
首先它是动词,而且不同于行为动词,行为动词表示的是可以通过行为来表达的动作(如写,读,跑),而情态动词只是表达的一种想法(如能,也许,敢).
用法是:情态动词+行为动词原形
例句:I can read this sentence in English.
我能用英语读这句话.
情态动词是一种本身有一定的词义,表示说话人的情绪,态度或语气的动词,但不能单独作谓语,只能和其他动词原形构成谓语.
We can be there on time tomorrow.我们明天能按时去那儿.
May I have your name?我能知道你的名字吗?
Shall we begin now?我们现在就开始吗?
You must obey the school rules.你必须遵守校规.
情态动词数量不多,但用途广泛,主要有下列:
can (could),may (might),must,need,ought to,dare (dared),shall (should),will (would),have (to) ,had better.
编辑本段功能
助动词(auxiliary)主要有两类:基本助动词(primary auxiliary)和情态助动词(modal auxiliary).基本助动词有三个:do,have和be;情态助动词有十三个:may,might; can,could; will,would; shall,should; must,need,dare,used to,ought to.上述两类助动词的共同特征是,在协助主动词构成限定动词词组时,具有作用词的功能:
1) 构成否定式:
He didn't go and neither did she.
The meeting might not start until 5 o'clock.
2) 构成疑问式或附加疑问式:
Must you leave right now?
You have been learning French for 5 years,haven't you?
3) 构成修辞倒装:
Nowhere can he obtain any information about his sister.
Hardly had he arrived when she started complaining.
4) 代替限定动词词组:
A:Who can solve this crossword puzzle?
B:Tom can.
A:Shall I write to him?
B:Yes,do.