第八讲 情态动词,考点一,考点二,考点三,情态动词是用于表示说话人对有关行为或事物的态度或看法的词,意为“可能”“应该”或“必要”等。 情态动词多数没有人称和数的变化,不能单独做谓语,只能和其他动词原形一起构成谓语。 情态动词具有助动词的作用,可用来构成否定句、疑问句以及用于简单答语。,考点一,考点二,考点三,Bill can sing the English song. 比尔会唱这首英文歌。 You mustnt smoke here. 你不可以在这儿吸烟。 May I come in?我可以进来吗?,考点一,考点二,考点三,典例1(2016江苏宿迁)I cant go with you.I stay at home until my parents come back. A.can B.may C.must D.could 解析:句意:我不能和你一起去。我必须待在家里直到我父母回来。must“必须”。故选C项。 答案:C,考点一,考点二,考点三,答案,解析,考点一,考点二,考点三,答案,解析,考点一,考点二,考点三,答案,解析,考点一,考点二,考点三,答案,解析,4.Mom, I go fishing with my friends now? Sure,but you make your bed first. A.can;need B.may;have to C.must;need D.need;must,考点一,考点二,考点三,考点二常见的情态动词,考点一,考点二,考点三,考点一,考点二,考点三,考点一,考点二,考点三,考点一,考点二,考点三,考点一,考点二,考点三,规律总结(1)情态动词过去式表示比原形更委婉的语气。 (2)have to有人称、数和时态的变化,表示受客观条件限制,意为“不得不”。例如: She has to take the bus to work. 她不得不坐公共汽车去上班。 (3)May.?句式的否定回答:No,.mustnt/cant. Must.?句式的否定回答:No,.neednt/dont have to. (4)must,should,may,might表示的可能性程度为:mustshouldmaymight。 (5)need用作实义动词,在否定句或疑问句中时要用助动词do引导;need to do sth.表示主动意义,need doing表示被动意义,相当于need to be done。,考点一,考点二,考点三,典例2(2016天津)Mum, I play football this afternoon? Sure,but you finish your homework first. A.may;could B.can;must C.can;mustnt D.may;cant 解析:句意:妈妈,今天下午我能踢足球吗?可以,但是你必须先完成你的家庭作业。can在此表示请求;must表示命令。故选B项。 答案:B,考点一,考点二,考点三,答案,解析,考点一,考点二,考点三,答案,解析,6.Can I borrow your ruler,please? Yes,you .But you must return it to me before lunchtime. A.have B.can C.Must D.used to,考点一,考点二,考点三,答案,解析,7.Someone is knocking at the door. It Miss Liu.She has called to meet me at this time. A.can be B.may not be C.must be D.cant be,考点一,考点二,考点三,答案,解析,8.How hard the rain is!What should I do? You take my umbrella if you want. A.will B.must C.may D.shall,考点一,考点二,考点三,考点三易混情态动词 1.have to和must (1)have to表示客观需要,意为“不得不”,有人称和时态的变化(has to;had to;will have to); (2)must强调说话人的主观看法,意为“必须,应该”; (3)否定形式的不同:must的否定形式是mustnt,表示“禁止,不应该”;have to的否定形式是not have to,表示“不必”,相当于neednt。例如: The boy had to stay at home alone because his parents both went to work. 那个男孩不得不独自待在家里,因为他的父母都去上班了。,考点一,考点二,考点三,We must go to school on time. 我们必须按时上学。 You dont have to(neednt)lend me your car because little children mustnt drive. 你不必借给我你的车,因为年纪小的孩子不能开车。,考点一,考点二,考点三,2.can和be able to (1)表示某种能力时,二者可通用; (2)can有现在时和过去时(could)这两种时态变化,be able to可用于各种时态; (3)若有助动词或情态动词时只能用be able to。例如: Jack could(was able to)swim at the age of five. 杰克在五岁时就能游泳了。 Well be able to fly to the moon soon. 不久我们就能飞往月球了。 3.cant,mustnt,neednt和may not cant表猜测,意为“不可能”;mustnt表禁止,意为“不准,不应该,不允许”;neednt意为“不必”;may not表猜测,意为“可能不”。,考点一,考点二,考点三,典例3(2016江西)You take me to the station.My brothers taking me. A.cant B.mustnt C.shouldnt D.dont have to 解析:句意:你没必要带我去车站。我哥哥会来接我。故选D项。 答案:D,考点一,考点二,考点三,答案,解析,考点一,考点二,考点三,答案,解析,考点一,考点二,考点三,答案,解析,考点一,考点二,考点三,答案,解析,考点一,考点二,考点三,4.maybe与may be maybe用于句首表示“可能,也许”,相当于perhaps;may be是情态动词may加动词原形be,意为“可能是”,在句中做谓语。两者可互换。例如: Maybe he is from Canada.=He may be from Canada. 他可能来自加拿大。 典例4 he puts it in your basket.You right. A.May be;maybe B.Maybe;maybe C.Maybe;may be D.May be;may be 解析:may be用于句中,maybe常用于句首,故选C项。 答案:C,考点一,考点二,考点三,答案,解析,考点一,考点二,考点三,答案,解析,考点一,考点二,考点三,答案,解析,15.Big animals can be a lot of trouble. you should get a small pet,like a goldfish. Thats a good idea. A.May be B.Might be C.Maybe D.Could be,考点一,考点二,考点三,答案,解析,16.Parents often ask their kids not to meet their Internet friends because the kids in danger. A.maybe B.cant be C.mustnt D.may be,