情态动词疑点解析

2014-09-26宋海燕

高中生·高考指导 2014年9期

关键词：肯定句情态语气

宋海燕

一、could和was / were able to表示能力时的区别

例1 The fire spread through the hotel very quickly but everyone _______ get out.

A. had to B. would C. could D. was able to

解析：答案为D。该题考查could和was able to的区别，两者都可表示过去的能力，但如果表示过去成功地做了某事，只能使用was/were able to。

二、shall的特殊用法

例2 One of our rules is that every student _______ wear school uniform while at school.

A. might B. could C. shall D. will

解析：答案为C。句意为“我们其中的一条制度是每个学生在校期间都必须穿校服”。关键词为rules，表示法律法规或制度规定时用shall。

例3 —I havent got the reference book yet，but Ill have a test on the subject next month.

—Dont worry. You _______ have it by Friday.

A. could B. shall C. must D. may

解析：答案为B。shall可用于含第二、第三人称的陈述句中，表示说话人对对方的命令、警告、允诺或威胁等，此处用于第二人称，表示允诺。

三、表示请求及其答语的用词选择

例4 —May I take this book out of the reading room？

—No，you _______. You read it here.

A. mightnt B. wont C. neednt D. mustnt

解析：答案为D。在用could/might表示询问或征求意见的问句中，肯定应答要用can或may来代替could或might，而在用may/might征求意见的问句中，否定应答要用cant/mustnt。

四、表示推测时must/can/could/may/might/should的区别

例5 Jack described his father，who _______ a brave boy many years ago，as a strong-willed man.

A. would be B. would have been

C. must be D. must have been

解析：答案为D。本题考查情态动词表示推测的用法。表示推测时，用must表示非常肯定，用may/might（用于肯定句）或can /could（用于否定句、疑问句）表示可能，用should表示根据事实或常理作出的较有把握的推测；后面加动词原形表示对现在情况作出的推测，加be doing表示对正在进行的事情进行推测，加have done表示对过去情况作出的推测。用must have been表示对过去事情的肯定推测。

例6 The World Wide Web is sometimes jokingly called the World Wide Wait because it _______ be very slow.

A. should B. must C. will D. can

解析：答案为D。本题考查的是can用于肯定句表示推测的特殊用法。can一般不用于肯定句中表示推测，但有时也可用于肯定句，表示一时的推测，意为“有时也可能”。句意为“万维网有时被打趣地叫成‘长等网，因为网速有时会很慢”。

例7 What do you mean，there are only ten tickets？There _______ be twelve.

A. should B. would C. will D. shall

解析：答案为A。考查情态动词表示猜测。表示根据事实或常理作出的较有把握的推测，用should。此句表示“按理应该有12张”，用should。

五、need用作情态动词还是实义动词

例8 As a result of the serious flood，two-thirds of the buildings in the area _______.

A. need repairing B. needs to repair

C. needs repairing D. need to repair

解析：答案为A。考查主谓一致和need的用法。句子的主语为two-thirds of the buildings，表示复数，谓语动词用原形。用作情态动词时，need无人称和数的变化，常用于否定句和疑问句。以need开头的疑问句，肯定回答时用must，而must开头的疑问句，否定回答用neednt或dont have to。用作实义动词时，need有人称和数的变化，后加sth.或to do sth.，need to be done相当于need doing。此句主语“三分之二的建筑物”与need后的repair构成被动关系，用need to be repaired 或need repairing。

六、“情态动词+have done”表示责备语气时的不同含义

例9 We _______ the difficulty together，but why didnt you tell me？

A. should face B. might face

C. could have faced D. must have faced

解析：答案为C。考查“情态动词+have done”表示责备语气，为高考热点之一。表示责备语气，常用四个句型：should/ought to have done（过去本应该做了某事），should not/ought not to have done（过去本不该做了某事），neednt have done（过去本不必做某事），could/might have done（过去本可以做某事）。表示“过去本可以做某事”，用could/might have done。

七、cant /couldnt表示最高级含义的句型

例10 I _______ thank you too much for all your help to my son while we were away from home.

A. wont B. cant C. can D. will

解析：答案为B。考查固定句型“cant /couldn t ...too+形容词或副词的原级”表示最高级的含义。常用的表达方式还有：cant/couldnt ...enough，cant /couldnt+形容词或副词的比较级，cant /couldnt ...so/such ...（as）等。

八、表示其他特殊语气的用词

例11 You cant imagine that a well-behaved gentleman _______ be so rude to a lady.

A. might B. need C. should D. would

解析：答案为C。本题考查的是should 表示惊讶、惊奇或出人意料这一特定语气，常用于it is a pity that/it is strange that等句型中。should 在这里表示“竟然”，句意为“你难以想象这么一位彬彬有礼的绅士竟然对一位女士那么粗鲁”。

例12 —Write to me when you get home.

— _______.

A. I must B. I should C. I will D. I can

解析：答案为C。will可以表示“一定，决心做某事”。