译林版（2019） 必修 第二册Unit 4 Exploring literature　Grammar and usage—Modal verbs 学案（含答案）

Period 3　Grammar and usage—Modal verbs 阅读以下语段，感悟黑体单词，并把序号填入表格内。 “What ①shall I read？” You ②might have asked yourself this question more than once.If you are not sure what to read，you ③can get ideas from different sources，but it is also important to develop your own taste. To start with，ask your friends，parents and teachers to recommend what books you ④ought to read.Most people will be happy to share their favourite books with others.Teachers in particular ⑤can provide suggestions for interesting reading materials that ⑥can be found in the library or bookshop easily.You ⑦could also read book reviews in newspapers，in magazines or online.A book review ⑧can often tell you whether a book is worth reading or not. These ideas ⑨should point you in the right direction.However，you ⑩must also decide for yourself what kind of books to read.You do not have to read a book just because everyone recommends it.Instead，look for books on topics that interest you.Take time to look through the collections in different sections of your local library，and you are likely to come across books you love to read.Over time，you may find yourself better able to seek out books to your taste and enjoy reading all the more. Suggestion Ability Necessity Possibility [自主发现] 以上黑体单词均为情态动词(Modal verbs)；其后必须要接动词原形；可以用来表示建议、推测、能力或必要性。 一、概述 情态动词本身有一定的词义，通常跟动词原形一起构成谓语，表示说话人的看法或主观设想。常见的情态动词主要有can，could，may，might，must，ought to，shall，should，will和would。另外，dare，need，have to和used to也具有情态动词的某些特性。 二、情态动词的基本用法 1．can与could的用法 (1)表示能力，此时could 是can 的过去式，意思相当于be able to。 My grandmother can do some shopping on the Internet，but she couldn’t last year. 我奶奶会网购了，但是去年她还不会。 [疑难点津] 在一般过去时中，was/were able to 通常表示经过一番努力能够做……，could 仅表示能力。 I was able to swim to the bank when the ship sank. 当船下沉时，我已经游到岸边了。 I could lift the heavy box. 我能把那个沉重的盒子举起来。 (2)表示可能性，一般用于疑问句和否定句中，can’t/couldn’t 意为“不可能”。 Can this news be true？这则消息可能是真的吗？ Your story can’t/couldn’t be true. 你的故事不可能是真的。 (3)表示请求和许可，could表示更委婉的语气。 —Can/Could I go now —Yes，you can. ———我现在可以走了吗？ ———是的，可以。 (4)表示理论上或习惯上的可能性，意为“有时会”。 As we all know，anyone can make mistakes. 我们都知道，任何人都可能会犯错。 2．may与might的用法 (1)表示允许、许可。might在语气上比may更委婉。 May/Might I play computer games after supper？晚饭后我可以玩电脑游戏吗？ (2)表示可能性，用于肯定句。 I think he may come tomorrow. 我认为明天他可能会来。 3．must与need的用法 (1)表示必要性。must意为“必须”，其否定式为mustn’t(不准，禁止)。need 意为“需要”，其否定式为needn’t(不必)。 You mustn’t do that，because you must keep your word. 你不准那么做，因为你必须得遵守诺言。 You needn’t do it if yo ... ...