Unit 8 Grammar语法 课件 2023-2024学年沪教牛津版英语八年级上册

Unit 8 English Week Grammar Modal verbs How many modal verbs have we learnt? What are they? can, could may must mustn’t need should, shouldn’t 情态动词should的用法 1. should在肯定句中可用来讨论义务和职责或提出建议，意为“应该”。如： You should pay more attention to spelling. 2. should后面跟动词原形。否定式should not，其缩略形式是shouldn’t，意为“不应该 ”。如: You should not / shouldn’t play football in the street. 3. should 用于疑问句，表示征求意见或请求指示。 如： — Should I call the police? — Yes, you should. / No, you shouldn’t. 4. should 还可以表示更正别人的说法。 — The total price of these books is 230.5 yuan. —No. That should be 232.5 yuan. Check it again. 注意：should和ought to均可用来谈论义务和职责或提出建议。两者 可以互换使用，不过should常用得多。 should和ought to的意思都是“应该；应当”，都表示义务或责任 should的语气比较委婉， ought to的语气比较强， 有时带有责备或督促的意味。 一般说来，两者可替换，ought to语气稍重。 情态动词 should 和ought to 1. must的意思与should和ought to类似，但语气更强或更肯定，表示“必须”之意，常含有命令的性质；should和ought to的语气则相对缓和些。如： You must give up drinking.你必须戒酒。 (说话者可能是医生，强调命令执行的必须性。) You really should / ought to give up drinking. 你真的应该戒酒。(可能是来自亲友的劝告。) should, ought to & must 2. should可以替代must使指示听起来更客气些。如： You should send the letter by 30 June. 你应该在六月三十日之前寄出这封信。 3. should和ought to可以用来预测，表示预期会发生什么事 情。must往往不这样用。如： 明天天气会好的。 It should be fine tomorrow. ( ) It must be fine tomorrow. ( ) √ × I. 按要求改写句子，每空一词。 1. You should visit your grandparents tomorrow. (改为否定句) You _________ _________ _________ your grandparents tomorrow. 2. They should go to college when they grow up. (改为一般疑问句) __________ __________ __________ to college when they grow up? should not visit 跟踪练习 Should they go 3. Lily should write a letter to her mother right now. (对划线部分提问) __________ __________ Lily __________ right now? 4. You ought to spend less than one hour watching TV.（改为同义句） You __________ spend less than one hour watching TV. 5. They should finish the work before 8 o’clock. (对划线部分提问) __________ __________ they __________ the work? What should