must表示推测.doc

must表示推测1) must用在肯定句中表示较有把握的推测，意为一定。2) must表对现在的状态或现在正发生的事情的推测时， must 后面通常接系动词be 的原形或行为动词的进行式。 You have worked hard all day.You must be tired. 你辛苦干一整天，一定累了。（对现在情况的推测判断）He must be working in his office. 他一定在办公室工作呢。比较： He must be staying there. 他现在肯定呆在那里。 He must stay there. 他必须呆在那。 3) must 表示对已发生的事情的推测时，must 要接完成式。 I didnt hear the phone. I must have been asleep.我刚才没有听到电话，我想必是睡着了。4) must表示对过去某时正发生的事情的推测，must 后面要接不定式的完成进行式。-Why didnt you answer my phone call?-Well, I must have been sleeping, so I didnt hear it.5) 否定推测用cant。 If Tom didnt leave here until five oclock, he cant be home yet.如果汤姆五点才离开这儿，他此时一定还未到家。be supposed to用作半助动词，其语法特点同have to, be about to, be bound to, be going to一样。其语义有三种：一、 be supposed to相当于ought to,表示按照规则、规律、义务或约定“应当”、“理应”去做某事。例1.Everyone is supposed to bring a bottle of beer to the party.每个人都必须带一瓶啤酒去参加聚会。例2.People under eighteen arent supposed to buy alcoholic drinks.十八岁以下的人不允许买含酒精的饮料。例3.He told this to somebody else, not realizing that he was not supposed to.他不知道这件事不该告诉别人，结果告诉别人了。【拓展】be supposed to 如果与完成时不定式连用，则表示“本应该做某事而实际上却没有做”。例如：1. He was supposed to have told me about it.他本应该把这件事告诉我的。2. Mrs.Brown is supposed to have left for Italy last week.布朗太太本应该上周动身去意大利的。【练习1】根据汉语完成句子：1、每个人都不应该随地吐痰。Everyone not spit.2、我们应该互相关心。We all care about each other.3、他上课迟到了，他应该早点起床的。He is late for class, he is have up.4、查克意识到他以前应该多关心他的朋友。Chuck realized that he was have more about his friend.二、 be supposed to作“一般认为”、“被看作是”解。、例1.I havent seen it yet，but its supposed to be a very good film。我还没看过这部电影，但一般认为这是一部很好的电影。例2.Li Dawei is supposed to be a good police, but I have not known him. 大家都认为李大伟是一名好警察，但我还不认识他。【拓展】be supposed to往往含有“事实并非如此”的意思。例如：1.You are supposed to be an expert, but you dont know very much about it.大家都认为你是个专家，可是你并不在行。2.Eric Cox was supposed to have died as a young man.人们都认为埃里克考克斯在年轻时就已经死了。【练习2】1.Mr.Led wasnt her father because he had never cared about her.A. suppose to beB. supposing to beC. supposed to beingD. supposed to be2.A pet one of the family in the USA.A. is supposed asB. is supposed to beC. is treated to beD. is seen as3.The students be Yin Xuemeis children, so her students were fond of her.（用suppose的适当形式填空）4.Ren Changxia is a very good policewoman. She be living well. （用suppose的适当形式填空）三、be supposed to表示“意图、意旨”、“将要、打算”。例1.The law is supposed to help the poor.那条法律旨在帮助穷人。例2.-Why dont you and Bill go to the movies tonight?你和比尔今晚为什么不去看电影？-We are supposed to take care of the old woman. 我们打算去照看那位老太娘。例3.The machine is not supposed to make noise.这台机器不会产生噪音。【拓展1】suppose v.意为“猜想，料想，假定”。例如：1. Lets suppose we each had 5 million yuan to spend, what would we buy with it? 我们大家来想想，要是我们都有5百万元来花，我们会买些什么？2.I dont suppose that he cares, does he ?我想他不会介意，是吗？【解析】在think, believe, suppose, expect等动词后面从句中，如果在意义上需要否定宾语从句的某个成分，常常要将否定转移到主句中去。这就意味着that从句实质上是个否定句，所以，这里的附加疑问句只能用肯定形式。【拓展2】suppose conj. 1.意为“假如”；2.用于提议，意为“让”。例如：1. Suppose he is lost, what would you do?要是他迷路了，你怎么办？2. Suppose we have lunch now！我们现在吃午饭好吗？3. Just suppose everyone were to give up smoking and drinking！让我们每一个人都戒掉烟酒吧。【解析】在正式英语里，suppose引出的宾语从句的谓语动词要使用虚拟过去时。主要是为了使所提出的建议变得客气、委婉、或者使提出的建议听起来不那么肯定。【练习3】根据括号里的提示完成各句子：1.-Lets go hiking tomorrow, will you? -Sorry, I （打算）visit my aunt.2.The law （意旨）stop cutting trees down.3. play football together！（我们一起去踢足球吧）4.Suppose we （go）to swim！5.We suppose that he can speak Spanish, ? （是吗）6.I dont suppose that he is thirty years old, ? （对吗）Keys:【练习1】1.issupposedto, 2.aresupposedto,