七年级英语electricity课件

七年级英语electricity课件内容摘要：

electricity, but we can change it into different forms of energy NO Who is looking foolish now, Benny There is a problem with the electricity in Benny’s flat. An electrician came to deal with this problem. Listen to the conversation between the electrician and Benny’s mother. Find out which things were on or off when the electricity stopped, and circle ON or OFF next to the objects. Before you listen, make sure you know the following words: Vacuum v. 用 真 空吸 尘 器 清扫 properly adv. 正确地 ,恰 当地 Iron ,烫 平 plug lights air conditioner fridge kettle washing machine television vacuum cleaner rice cooker iron ★ Language 情态动词 情态动词不能单独作谓语动词，后接其它动词 原形做谓语，没有人称和数的变化。 1. 表示能够或不能做某事用 can 或 can’t A bird can fly . Fish can’t live without water. 2. 告诉人们必须或禁止做某事用 must或 mustn’t You must hand in your homework at once. You mustn’t talk loudly in public. 3. 表示请求或允许做某事 may 或 can May I e in ? Can I open the door ? 4 .谈论该做或不该做某事用 should , ought to 或 shouldn’t , ought not to She should do her homework first . They ought to finish the work on time . they ought not to be late for school . ★★★ Notes : can 和 be able to的区别 : be able to 有 人称数和时态的变化。 I can e tomorrow . I will be able to e tomorrow. 在回答 must的疑问句时，否定回答常用 needn’t 或 don’t have to表示不必，而不用 mustn’t。 Must we stay here ? No, you need n’t . ( No, you don’t have to .) must be 表示肯定的猜测，意为“一定 ……” can’t be 表示否定的猜测，意为“ 不可能 ……” She must be a nurse . I saw her in the library just now .She can’t be here .。