哪些情况从句的谓语动词用should do

哪些情况从句的谓语动词用should do
哪些情况从句的谓语动词用should do

哪些情况从句的谓语动词用should do
在“It is suggested/proposed/ordered/a pity/no wonder/necessary/strange/…＋
that从句”结构中,that从句谓语有时用（should）do这样的虚拟语气形式.
例如：It is suggested that we(should) improve the relations between us.
It is a pity that one(should) stay in one place all one´s life.
It is strange that she should have failed to see her own shortcomings（缺点）.
请看NMET2003第37小题：
When Ed firs phoned and ____ we play,I laughed quietly,figuring on an easy victory.
A.declared B.mentioned C.persuaded D.suggested
析：解该题需从两个方面入手.首先,从上文的phone d可知,Ed要约我去打墙网球,故选suggested(建议).从另一个角度看,四个选项都为过去式,而后面的宾语从句为we play这种虚拟句式.我们知道,只有表"建议"、"命令"、"要求"等意义的动词后面才能跟(should)do的虚拟句式,故选D.
谓语动词须用(should)do的虚拟语气句式(我们简称为should do句型),贯穿于高中教材的始末,频频出现在宾语从句、主语从句、同位语从句及表语从句中.现为同学们总结如下,希望会对同学们的学习有所帮助.
1.表示"坚持(insist,urge),命令(order ,command),建议(advise,suggest,propose),要求(ask,beg,urge,require,request,demand),决心(decide,determine),同意(agree),安排(arrange)"等意义的动词引导的宾语从句的谓语须用should do的形式,should可以省略.例如：
They agreed that the roof(should)be repaired.他们同意应该修理屋顶了.
They arranged that the new mayor(should)be met at the airport.他们安排在机场迎接新市长.
注意：含有以上动词所引导的主语从句的谓语也要用(should)do的形式.例如：
It's ordered that they(should)arrive at the front before dawn.他们接到命令,天亮前务必赶到前线.
再者：由以上动词转化来的名词所引导的同位语从句的谓语也要用(should)do的形式.例如：
It's a good suggestion that the meeting(should)be put off till next week.会议推迟到下周真是个好建议.
2."be anxious"及"be determined"所引导的从句的谓语须用(should)do的形式.例如：
They are determined that they(should)keep SARS under control in this are a.他们决心将该地区的SARS疾病控制住.
3.在句型"It is /was＋形容词＋that从句"中,如果形容词是important,necessary,natural,better ,reasonable,fair ,just,right,advisable,desirable等时,那么that引导的主语从句的谓语就应该用should do的形式,有时省略should.例如：
It's better that he(should)hear it from you.最好他从你那儿听到这件事.
It's advisable that everyone(should)have a map.有人建议每人都要有一份地图.
4.若句型"It is /was＋形容词＋that从句"中的形容词是表示"惊诧""疑惑"意义的形容词,如strange,surprising,shocking,amazing等,那么该主语从句的谓语就要用(should)do的形式,should可以省略.例如：
It's surprising that we(should)be short of water in a country Where it often rains .在一个多雨的国家,我们竟然缺水,真是奇怪.
It's amazing that s he(should)haves aid nothing about the murder.她竟然对那起谋杀案只字未提,真令人费解.
注意：若以上句型中的形容词变成相应意义的名词,如surprise,wonder,amazement等,那么that引导的从句也应该用(should)do的形式.例如：
It's a great surprise that he(should)read ten books a day.他竟然能一天读十本书,真令人吃惊.
再者：若上面的形容词变成相应的表示人的形容词,如surprised,shocked,amazed等,那么该形容词引导的从句的谓语也要用(should)do的形式.例如：
I'm surprised that you(should)speak in such away.我很惊讶你居然用那种口气说话.
5.should用在can't think why,don't know why,see no reason why等后面,表示说话人对假设的合理性或正确性持怀疑态度,此时should不能省略.例如：
I don't know Why you should think that I did it.我想不通,为什么你认为是我做了这件事.
I see no reason Why you should interfere in their quarrel.我不明白为什么你涉入他们的争吵.
注意：在这些句型中,通常用不定式的完成式来表示对过去的假设.例如：
I can't think Why he should have said that it was my fault.我不明白他为什么说那是我的错.
6.should习惯上与疑问词what,where,who,why等连用,表示"意外,纳闷,惊讶",使惊异表达得富于戏剧性,此时should不能省略.例如：
Why should you think that way?你怎么能那么想呢?
Who should come in but my old friend Betty!我以为是谁进来了,原来是我的老朋友贝蒂呀!
7.should用在lest或in case之后的从句中.例如：
(1)书面语中lest...should有时用在表示恐慌或焦虑的词语后面.例如：
He was terrified lest /in case he should slip on the ice .他害怕在冰上滑倒了.
注意：如果这种焦虑与先前的某个动作有关,则用"should＋have done"的形式.例如：
She began to be worried lest /in case he should have met with some accident.她开始担心万一他出了什么事故.
(2)lest也可用在目的状语从句中,意为"for fear that".例如：
He dare d not to spend the money lest /in case some one should as k Where he had got it.他不敢花这钱,惟恐别人问及钱的来路.
He ran aw ay le s t /in case he should bear rested.他害怕被捉住,就跑掉了.
8.should用在条件句中,代替现在时态,表示该动作虽然有可能发生,但可能性不大.它通常与一个祈使句连用,主要用于书面的说明文字中.例如：
If the pain should re turn,take another of the s e pills .如果再痛的话,就再吃一片药.
If the s e biscuits should arrive in a damaged condition,please inform the factory at once .如果发现这些饼干在购进时有问题,那么就要立即通知厂方.
注意：在这类句型中,我们可把should放在句首,省去if.例如：
Should you require anything,please call me.如果你需要什么东西,请叫我一声.
题是贴上去的.呵呵

命令语气，虚拟语气，还有说话者觉得对方有责任做某事时。