Module 12 Unit 3（配套课件）-【鸿鹄志·名师测控】2023-2024学年八年级上册英语（外研版）

Unit 3 Language in use Module 12 Help 外研·八年级上册 —What are they doing? They ____ _______ the building quickly when the ground stops shaking. are leaving Lead-in What are they doing? They are _______ _______ a table. hiding under What is he doing? He is ________ ______ from the sea and moving quickly to higher ground. running away 祈使句表达说话人对对方的叮嘱、劝告、希望、禁止、建议、请求或命令等。 祈使句一般以动词原形开头，无时态和数的变化。 一、祈使句 暗含的主语是you，通常省略。否定句往往由do not (don’t)或never开头。祈使句的句首或句末有时加please,还可以加上称呼语，用逗号与句子主体隔开。 1. 动词原形构成的祈使句 常见的句型如下: Have a nice day! Don’t waste your time! Never be late again! Come this way, please. Please be quiet, boys! Make sure he’s warm. Don’t use the lift. 例: 2. Let’s 构成的祈使句 这类祈使句往往用于提出建议。 例: a) Let’s spend this weekend in the countryside. b) Let’s take a taxi, shall we? 在请求、命令和口号中，常用无动词祈使句， 它实际上是省略了动词，从而使语句更简洁有力。 例: a) Just a minute, please! b) This way, please! 3. 无动词祈使句 情态动词can和could表示“能够，可以”等意义的用法。还可表示对现在或将来的推测，意为“会，可能”，但can表示推测时，往往用于否定句和疑问句。用于疑问句时，can比could表示的“可能性要大；用于否定句时，can’t表示“不可能”。 例: You can’t be serious! 二、情态动词must/can/could表示推测 could则可用于肯定句、否定句和疑问句。 在以下例句中,can和could均表示可能: a) He could be in pain. b) That could be harmful! c) Can/Could this be true? 情态动词must也可以表示猜测, 意为“一定，准是”，通常只用于肯定句。 例: Betty, you must know. — Who sent the present? Can it be your brother? (表示不可能) 对比下列一组句子: (询问可能性) — It must be your brother. I saw him in your room just now. (语气强烈， 表示非常肯定) — It can’t be my brother. He is still in France. Language practice That ______ be harmful! Betty, you ______ know! _____ _____ from windows and heavy furniture. 4. ______ ______ _____ street lights or under power lines. Stay away must could Don’t stand near 1 1. It is dangerous. You ______ keep out! 2. These stairs are not safe. You ________ use them. 3. The rocks are falling down. You ______ get hit. 4. The river is too deep. You _________ swim in it. 5. Betty ______ know what to do because she d