1、情态动词（modal verbs）情态动词主要用来表示说话人的看法、意愿、态度等。从用法上来说，它有如下几个特点：情态动词本身都有一定的词义；情态动词单独不能在句子中充当谓语；情态动词没有人称和数的变化；情态动词后接都不带 to 的不定式（除 ought 外） ，即接动词原形。常用情态动词的基本用法1. can she shant be pressed.我不想对你女儿太严厉, 她不会太受压的。2) 表示命令You shall come to my office immediately. 你必须马上来我的办公室。She shall not stay in my garden. 她不许呆在我的花园
2、里。3) 表示必然That day shall come. 那一天一定会到来。This law shall come into effect on January 1st 2007.这项法律于 2007 年元月 1 日生效。4) 表示约定The renter shall keep the house in a neat and orderly state.租赁者要保持房屋整洁有序。The supplier shall make shipment before October and the purchaser shall make payment within 15 days after re
3、ceipt of the goods.卖方十月以前装运, 买方在收到货物后十五天内付款。（2 ） ought to 表示“应该” ，口气比 should 还要强。它的否定式为 ought not to/oughtnt to。 You ought to take care of yourself when Im away. 我不在的时候你一定要照顾好自己。 You oughtnt to have let out the secret. 你本来不应该泄露这个秘密。（3）should 应该1) 表示出于职责、义务该做某事You shouldnt come to such a decision has
4、tily. 你不应该匆匆忙忙地作出这么一个决定。We should read English aloud every morning. 我们应该每天早晨朗读英文。2) 表示对某种情况的估计She shouldnt be out in such an early morning. 她不会这么一大早就出去了吧。This book should be published in two months at most. 这本书最多两个月后就会出版的。3) 用于某些从句中表示虚拟语 气The doctor insisted that the girl should be hospitalized.大夫坚持
5、认为那个女孩要住院治疗。If it had not been for the doctors care, the girl should not be speaking to you now.要不是由于大夫的精心照料, 这个女孩现在就不能与你说话了。【小试牛刀】1. Johnny, you _ play with the knife, you _ hurt yourself.A. wont; cant B. mustnt; may C. shouldnt; must D. cant; shouldnt 2. Shall I tell John about it?No, you _. Ive t
6、old him already.A. neednt B. wouldnt C. mustnt D. shouldnt3. You _ take your umbrella. Im sure it wont rain.A. shouldnt B. cant C. dont have to D. mustnt4. She _ for what she has done. But why do you keep silent on it? A. ought to praised B. ought to have praised C. ought to have praised D. ought to have been praised 【答案及解析】1. B【解析】根据句意可知，应该是禁止 play with the knife。第一空填 mustnt，所以选 B。2. A【解析 】根据句意 “我已经告诉他了 ”可知，应该选 A，没有必要。3. C【解析】根据第二句“我确定不会下雨”可知，应该是“没有必要带伞” ，故选 B。4. D【解析】根据句意可知，是被表扬，应用被动语态，所以选 D。gkstkgkstkgkstk版权所有：学优高考网()
