1、返回目录 Healthy eating Unit 2 返回目录 Section Grammar情态动词()返回目录 课堂要点精析课末随堂演练课后限时作业目录Contents 返回目录 课堂要点精析1had better 的用法(1)had better 为情态动词，可缩写为d better，没有人称和数的变化，意为“最好；还是好”，其后接不带 to 的不定式。had better 表示现在或者将来“最好”，而不指过去。You had better write to your parents once a month.你最好每个月给你父母写一次信。返回目录(2)had better的疑问形式通常
2、是把had提前，放在句首。had better在陈述句中的否定形式同在疑问句中的形式是不同的。在陈述句中，not放在better后；在疑问句中，not可放在主语后和better前，也可放在had后和主语前。返回目录 Had I better do my homework?我最好做家庭作业吗？Youd better not play football in the street.你们最好别在街上踢足球。Hadnt you better/Had you no better give up smoking?你是不是最好把烟戒掉？返回目录 2need 的用法need 既可以作实义动词，也可以作情态动词
3、。作情态动词时，后跟动词原形，表示“需要；有必要”，无人称和数的变化，多用于否定句、疑问句或条件句中。You neednt come today.今天你不必来。Why need you go today?你今天为什么一定要走？返回目录【提示】(1)由 need 引导的一般疑问句，肯定回答常用 must或 have to，否定回答常用 neednt。Need I answer the question?Yes,you must./Yes,you have to./No,you neednt.我须要回答那个问题吗？是的，你必须回答。/是的，你得回答。/不，你不必回答。返回目录(2)need 作实义
4、动词时，常用于下列搭配中：need to do主语与do为主谓关系need doing/to be done主语与do为动宾关系The boy needs to look after his younger sister.这个男孩需要照顾他的妹妹。His younger sister needs looking after/to be looked after.他的妹妹需要被照顾。返回目录 3dare 的用法dare 既可以作实义动词，也可以作情态动词。作情态动词时，后跟动词原形，多用于疑问句、否定句和条件状语从句中。一般疑问句形式是：Dare he/they/you？否定形式为 darent
5、。How dare she do things like that to me?她怎么敢对我做那种事？返回目录 Dare you catch the mouse?I darent do that.你敢去抓那只老鼠吗？我不敢。If you dare say that to our teacher,I would vote for you.如果你敢跟我们老师说那件事，我就投你一票。返回目录【提示】dare 作实义动词时，常用于 dare to do sth 结构中，在否定句中不定式符号 to 也可以省略。The children dont dare(to)make a sound while th
6、eir parents are sleeping.孩子们在父母睡觉时不敢弄出一点声音。返回目录 4ought to 的用法(1)表示责任和义务，意为“应该”，与 should 同义。否定形式为 ought not to(oughtnt to)；一般疑问句形式是将 ought 置于主语前，其否定答语通常用 doesnt/dont have to 或 neednt。返回目录 You oughtnt to drive if you are feeling tired.你要是觉得疲劳的话就不该开车。Ought he to see the doctor?Yes,he ought to./No,he do
7、esnt have to./No,he neednt.他该去看医生吗？是的，他该去。/不，他不必去。/不，他不需要去。返回目录(2)表示可能性，一般指较大的可能性，意为“按道理应该”。They ought to be at work by now.他们现在应该在上班。返回目录【提示】should 表示自己的主观看法，而 ought to 语气重，含有“按道理该”之意，如果要反映客观情况或涉及法律义务和规定时一般用 ought to。We ought to protect rare animals from being hunted.我们应该保护珍稀动物免遭猎杀。返回目录 5情态动词表示推测的用
8、法情态动词使用场合对现在和未来事情的推测对过去事情的推测意思must肯定句must动词原形must have done一定，准是may/might肯定句、否定句may/might动词原形may/mighthave done可能，也许can/could否定句、疑问句(could可以用在肯定句中)can/could动词原形can/couldhave done可能，也许should肯定句、否定句、疑问句should动词原形(用来表示一种估计的情况)should have done按理会，估计会返回目录 The story he told us must be true.他告诉我们的故事一定是真的。I
9、t may/might have rained during the night.夜间可能下雨了。The boy is honest.He cant tell lies/a lie.那个男孩很诚实，他不可能撒谎。It is nearly seven oclock.Mr Bernard should be here at any moment.快到七点钟了，Bernard 先生随时都会到这儿。返回目录 6“情态动词have done”的用法(1)must have done 表示对过去已经发生的事情进行推测，通常只用于肯定句中，意思是“一定做了某事”。在否定句与疑问句中分别用 cant 和 ca
10、n。The glasses are broken.It must have been done by the boy.玻璃杯碎了，肯定是那个男孩打碎的。Can you have informed her?你肯定你通知她了吗？He cant have lied to us,for he is very honest.他不可能对我们撒谎，因为他非常诚实。返回目录(2)may/might have done表示对过去已经发生的事情的推测，意思是“也许”，might的语气比may弱，主要用于肯定句或否定句。might have done也可以表示“本来某事可能发生，但实际上并没有发生”；还可以表示“本
11、来应该或可以做某事”，含有轻微的责备意味。返回目录 He may not have heard of the news.他可能还没有听说这个消息。You shouldnt have run in the street.You might have been knocked down.你不应该在街上跑，你可能会被撞倒的。返回目录(3)should/ought to have done 用于肯定句，表示“本应该做某事，而事实上没有做”；用于否定句，表示“不该做的事情反而做了”。You should have done more exercise before.以前你应该多做一些锻炼。We ough
12、t to have gone there by taxi.我们本应该乘出租车到那里去的。返回目录(4)neednt have done 表示“做了本来不必做的事”。注意didnt need to do 表示“没必要做某事而实际上也没有做”。You neednt have told me the news.I have already known it.你本不必告诉我这个消息，我已经知道了。I didnt need to paint the chair.My father did it.我不必刷这把椅子，我父亲刷过了。返回目录(5)had better have done 用于事后的建议，含有轻
13、微责备的意味，意思是“当时最好做了某事”，其否定形式为 had better not have done。You had better not have scolded her.你当时没有责备她就好了。(6)would rather have done 表示“宁愿做了某事”。I would rather have called on him last week.我宁愿上周去拜访他了。返回目录(7)could have done 用于肯定句，表示“可能已经”，此外，还可以表示过去没有实现的可能性，意思是“本来可以但是”。You could have done it well,but you we
14、re too careless.你本来可以做好它，但是你太马虎了。返回目录 单句语法填空1My room is a mess,but I _ clean itbefore I go out tonight.I can do it in the morning.2My book,The House of Hades,is missing.Who_ have taken it?3The children _(get)lost in thewoods;otherwise,they would have been at the lakeside课末随堂演练neednt could must have
15、got 返回目录 4 I_(enjoy)myselfmoreit was a perfect day.5(2018天津卷改编)I cant find my purse.I_(leave)it in the supermarketyesterday,but Im not sure.couldnt have enjoyed could/might have left 返回目录 语法与写作1如果我需要你来帮助我，我会毫不犹豫地打电话给你。_，Illcallyouwithout any hesitation.2(2017江苏卷书面表达)因此，电影行业应该做出更大的努力以吸引更多的观众。Therefor
16、e,thefilmindustrymoreIf I need you come and help me should make greater effortsto attract 返回目录 3我意识到我不应该在没获得你的许可的情况下打开并阅读信件。IrealizethatI_without yourpermission.4你本应该早点告诉我这次旅行的事情，不然的话我就会和他们一块去了。You_aboutthetravelIthemought not to open and read the letter should have told me earlier might have gone with 返回目录 5他的办公室的灯还亮着，此刻他一定在那里工作。The light is on in his office.He _there at the moment.must be working
