1、,表示推测的情态动词的用法 情态动词可以表示推测。常见的有：can, may, must, should, could, might等。,(一)用于肯定推测的情态动词 1must 表示较有把握的推测，意为“准是；一定”，后接动词原形，表示对现在的推测。例： The workers must be very tired, because they have been working for about 48 hours.工人们肯定很累，因为他们一直工作了大约48小时。,2should 用于肯定句中，语气次之，意为“很可能；应该”，指按常理推测。例： They left yesterday.The
2、y should be home by now. 他们昨天就离开了。现在该到家了。 3can用于肯定句中，表示理论上的可能性。例： Smoking can cause cancer. 吸烟有可能引起癌症。,4may用于肯定句中，表示对现在把握不大的推测，意为“也许”。例： Please ask the policeman over there.He may know the way.请问那边的警察。他也许知道那条路。 5could, might 常用在过去时态中，意为“可能”。但在某些场合下，为了使语气更缓和、更委婉，常用could, might 代替can。例： The dictionary
3、 could/might be Li Leis. 这本词典可能是李雷的。,(二)用于否定推测的情态动词 1cant/couldnt表示否定推测，语气最强，指“不可能”，带有惊异、怀疑的感情色彩。例： The door is locked.He cant be at home. 门锁着，他肯定不在家。 2may/might not表示推测，语气不很肯定，意为“可能不；也许不”。例： He may not/might not come back. 他可能没回来。,(三)用于疑问推测的情态动词 can/could常用于疑问句的推测，意为“可能”。例： Who can it be? Can it be
4、 Mary? 那能是谁呢？是玛丽吗？,单项选择 1Where is our teacher? I think she _ be in the office, but Im not sure. Amust Bmight Chave to Dshould 解析：答句句意：我认为她可能在办公室里，但是我不确定。must“一定”；might“可能”；have to“不得不”；should“应该”。,B,2Look！Is that man over there our math teacher? It _ be him.He has gone to Hong Kong. Amight not Bcoul
5、dnt Ccant Dmustnt 解析：由答语后半句他去了香港，可推知一定不是他，表否定推测用cant。,C,3The light in his room is on.He _ be in it. Amust Bshould Cwould Dcant 解析：句意：他房间的灯亮着。他一定在里面。表肯定推测用must。,A,4Mary _ for her English test because she wants to get a good grade. Amust studying Bmust be studying Cmight studying Dcant be studying 解析：
6、对正在发生的事情的推测用“情态动词be动词ing形式”结构。,B,5Whats the matter with Tom？He has been absent for two days. Oh！He be ill.Lets go and ask Ms Brown. Acan Bneed Cmay Dwould 解析：答句句意：噢！他可能病了。让我们去问问布朗女士吧。may用于肯定句中用以表达不是很肯定的推测，意为“也许”。故选C。,C,本单元围绕“物品所属”这一话题提出假设，做出推论，按照推断的可能性的大小正确使用表示推测的情态动词must, may, could, might, cant 等进
7、行推测。根据情境，进行推测、判断之类的作文是本单元测试和中考常考的话题作文之一。,假如你是Mike，你的好朋友Lucy的宠物狗豆豆，走失好几天了，为此，她感到焦虑。请给Lucy写一封信，安慰她，并推测狗可能会在哪里，在做什么。 要求： 1书信格式要正确。 2运用以下句式给出猜测： She might. It is possible that. 380词左右。,Dear Lucy， Im sorry to hear that your pet dog has been lost for several days.You neednt worry about her.She might be tr
8、ying to find out the way home now.Or she might meet a kind person and be sent to the police station.And also it is possible that she may be playing somewhere with some other dogs.I think she will come back home sooner or later. Best wishes! Yours， Mike,【思路点拨】 1这是一篇应用文。 2以第一人称来写。 3用情态动词做出推测。,1(2016绵阳
9、)Is Mr.Brown driving here? Im not sure.He come by train. Amay Bshall Cneed Dmust 解析：may“可能”；shall“将要”；need“需要”；must“一定，必须”。根据Im not sure可知此处表推测，他可能会坐火车来，故选A。,A,2(2016福州)Look at the young lady in red.Is it Mrs.King? No.It be her.She is wearing a white dress today. Acan Bmay Cmust Dcant 解析：根据“She is w
10、earing a white dress today”可知她今天穿了一件白色的连衣裙，所以穿红衣服的女士不可能是金夫人，故选D。,D,3(2016泉州)Whats wrong with Judy？She has been absent for two days. Oh, she be ill.Lets go to ask Mr.Green. Amay Bneed Cwould 解析：根据“She has been absent for two days.”可知她缺席了两天了，可以推断她可能病了，故选A。,A,4(2016黔南)All passagers go through safety check before they take a plane. Acan Bmay Cmust Dought 解析：can“能，能够”；may“可以，可能”；must“必须，一定”；ought“应该”，故选C。,C,5(2016长沙)Finally, they came back. They be hungry after such a long walk. Acant Bmust Cneednt 解析：cant“不可能”；must“一定，必须”；neednt“不必”。根据after such a long walk可知走了这么长的路他们一定饿了，故选B。,B,感 谢 观 映,
