或许打个折，写个新的招牌，他能够赢回顾客。 (1)discount n．折扣 vt.打折扣，不重视
归纳拓展：at a discount打折扣 at a discount of...＝at a．..discount打……的折扣 品味典例：The shoes in that shop never discount. 那家店的鞋子从来不打折。 In this shop，everything is sold at a discount. 在这家商店，所有的东西都打折卖。
小试牛刀：完成句子
①Members of the club can buy anything in the shop_________________(以折扣价)． ②She bought a new dress_____________________(以五折)． (2)win...back赢回；重新获得
品味典例： Once you break your promise，you will never win back her trust again. 你一旦违背诺言将永远不会再赢回她的信任。
She tried to win her confidence back. 她努力赢回了她的自信。
小试牛刀：完成句子
③我怎样才能重新获得她的爱和信任呢？How can I_________ _her love and trust? ④他最终赢回了三年前他失去的东西。
Finally he won back_______ __ __3 years ago. 3．consult vt.咨询；请教；商量；查阅；查找
However，as she was so afraid of being laughed at by her friends，she did not consult a doctor but lived on a diet of rice，raw vegetables，bananas and lemons.(P12)然而，因害怕被朋友们嘲笑，她没有向医生咨询，而是以米饭、生蔬菜、香蕉和柠檬为主食。 归纳拓展：consult sb.about sth.向某人咨询某事
consult with sb.(about/on sth.)(就某事)与某人商量
品味典例：He consulted the teacher about the usage of it. 他就it的用法请教了老师。 小试牛刀：根据句意填入恰当的介词
①家长可以向老师询问孩子们的情况。
Parents can consult the teachers___________their children.
②我和朋友商量一件事。 I consulted__________a friend__________a matter.
课堂展示：展示前面5短语的重点用法及背诵老师要求的句子。 达标练习：I.完成句子
1. She couldn't have anyone _________ _________her room without permission. 她不容许任何人在未经许可的情况下进入她的房间。 2. If you cheat in the exam，you'll never_____ ______ _______ it.
如果你在考试中作弊，你会受到惩罚的。
3. He promised his mother never to _______ _______her again. 他答应他母亲再也不向她撒谎了。
4. All the clothes were bought____ _____ ________ _____ 20%/at a 20% discount. 所有的衣服都是以八折的价钱买的。
版权所有：高考资源网(www.ks5u.com)
Unit2 P4 语法情态动词(Ⅱ)
改编：李慧
学习目标：1. 理解并掌握本节情态动词的用法 2. 学会使用情态动词 自主合作探究： 1．ought to
(1)表示责任和义务，意为“应该”，与should同义，但语气比should重，侧重于“责任、
义务、道德、法律”等方面。
You ought to work harder than your brother. 你应该比你哥哥学习更努力。
【提示】 ought to的否定形式为ought not to(oughtn't to)；一般疑问形式是将ought提至句首，其否定答语通常用don't have to或needn't。 —Ought he to see the doctor? 他该去看医生吗？
—Yes，he ought to./No，he doesn't have to. 是的，他该去。/不，他不必去。 You ought not to make this kind of mistake again. 你不应该再犯这种错误了。 (2)表示可能性，一般指较大的可能性，意为“按道理应该”。
If he started at six，he ought to be here now. 要是他6点就出发的话，这会儿该到这里了。
2．have to/don't have to/mustn't
(1)have to表示客观上的必要性，意为“不得不”。由于它是由“have＋to”构成，因此它有多种时态变化形式以及人称和数的变化，其疑问句式和否定句式由助动词do构成。 It's too late. I have to go home now. 天色太晚了，我现在得回家了。 Did you have to leave now？你现在必须得走吗？
We don't have to go to school on Sundays. 星期天我们用不着上学。
(2)have to的否定式don't have to，表示没有义务或没有必要做某事，意为“不必”，常可以回答以must开头的疑问句。而must的否定式mustn't表示“禁止，不许”。 You don't have to finish the work now. 你现在没有必要完成这项工作。
—Must we hand in our homework this afternoon? 我们必须今天下午交家庭作业吗？ —No，you don't have to/you needn't. 不，你们不必。(肯定回答为：Yes，you must.) (3)have to表示客观需要，而must则表示主观的看法。
You must obey the rules of your school. 你必须遵守学校的规则。 I have to go now because it's getting dark. 天快黑了，我必须得走了。 3．need
(1)need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 needn't explain too much to me. 你没有必要给我解释这么多。
【提示】 由need引导的一般疑问句的肯定回答常用must或have to，否定回答常用needn't。 —Need I hand in my paper now? 我现在需要交上论文吗？ —Yes，you must./No，you needn't. 是的，你必须。/不，你不需要。
(2)用作实义动词，有动词的各种形式变化，可用于各种句式；其宾语可以是名词、动名词、动词不定式或代词；构成否定句和疑问句时要借助于助动词do或does。 We don't need to tell him the truth. 我们不需要告诉他真相。 He needs our help.他需要我们的帮助。
The bike needs repairing.＝The bike needs to be repaired.这辆自行车需要修理。 【提示】 need作实义动词时常用于下列句式： 主语＋need(s)＋to do(主语与to do之间为主谓关系)
主语＋need(s)＋doing/to be done(主语与do之间为被动关系) 主语＋need(s)＋n. 4．情态动词＋have done结构的用法 (A/B)
(1)must＋have done表示对过去发生事情所作出的合理或确有把握的推测，意为“想必/准是/一定……”，只用于肯定句中，在否定句或疑问句中通常被can/can't＋have done代替。
From what you said，she must have told you all about it.从你所说的来看，她一定把一切都告诉你了。
(2)can have done一般用于疑问句和否定句中，用于表示对过去所发生事情的推测。could have done用于肯定句时，表示“可能已经做过某事”或“本有能力做某事而未做”。 I couldn't have finished the job on time without your help.没有你的帮忙，我不可能及时完成这项工作。
you could have been more careful.你又犯错了，你本能更仔细些的。 (3)should/ought to have done
should have done表示过去本应该做，但实际上没做。
shouldn't have done/ought not to have done表示过去本不应该做，而实际上做了。 You shouldn't have told him the secret. 你本不应该告诉他这个秘密的。 You should have told me earlier or I might have gone with them. 你应该早点告诉我，不然的话我就会和他们一块去了。
(4)need have done表示“本需要做而实际未做”；needn't have done表示“本不必做某事而实际做了”。
You need have done it instead of him yesterday. 昨天你本需要代替他做那件事的。 You needn't have told them about it. 你本来没有必要告诉他们那件事。
(5)may/might have done表示对过去发生的事情的推测，意思是“也许已经做了某事，可能已经做了某事”，多用在肯定句中，用might时表示语气更加不肯定。 You might have read about it in the papers. 你可能已经在报上看过这个消息了。 课堂展示：让学生在黑板上默写出重点句式结构并写出例句。
达标练习：
用情态动词和括号内动词的正确形式填空（注意时态）
1．Hurry up！We______ __(go) to school right away. 2．Her eyes are red. She______ _ _ (be) crying.
3．I have no bike，so I________ (go) to the office on foot. 4．You_______ _(not buy) a gift，but you can if you want to. 5．Look！The road is wet. It_______ _(rain) last night. 6．You_______ _(give) some advice. He was too upset at that time. 7．You_______ _(smoke) in this part of the hospital. 8．There was plenty of time. She______ __(hurry)． 9．Bob________ (not speak) to his mother like that.
10．You_______ _(come) here on time，or you'll be fired next time.
版权所有：高考资源网(www.ks5u.com)
Book3 Unit2 Period 5
编写： 李慧
学习目标： 1 . 阅读课文，进一步理解故事情节，回答问题
2. 熟记和使用本节知识点
自主合作探究：
I阅读P14－15的课文，选择最佳答案