八年级下lesson25.pptVIP

Fill in the blank. He __________ (walk) when he met Tom on the street. _______ you _______(play) football at 9 o’clock on Sunday morning. When I got home, my mum ___________(cook) for supper. He ______________( not watch) TV at half past 8yesterday evening. REVISION was walking Were playing was cooking wasn’t watching Lesson 25 Let’s Do an Experiment! New words in lesson25 science n. 科学 experiment n. 实验;试验 theory n. 理论;学说 fill v. 装满 jar n. 广口瓶 upside n. 上部;上边 prove v. 证明;证实 observe v. 观察;监视 A“ theory” is an idea. A theory predicts what will happen. An experiment shows what happens. Do you think what will happen? Listen to the tape and answer the following questions. Have you ever done experiments? Do you think the cardboard will be down? Which theory is right, Brian’s or Danny’s? Can you do the experiment? Language notes I fill a jar with water. I cover the top with a piece of cardboard. 1. fill …with 用…把…装满 常用作 be filled with eg: She filled the bag with books. The bag was filled with books. 2. cover…with 用…把….覆盖 常用作 be covered with eg: They covered the seeds with earth. The seeds were covered with earth. 辨析 fill 与 full fill vt. 装满,充满,使….满 .如果表示装满了什么东西时,跟介词with. eg: Please fill the box with apples. full adj. 满的,充满的. 多作表语,表示主语所处的状态,常与of连用,另外full还有”饱了”的意思 eg: The classroom is full of the students. I’m full. Language notes ii. I’m not sure. = I’ve no idea. =I don’t know. iii. I’m sure the floor won’t get wet. be sure 确信的;有把握的,常用结构: be sure of; be sure+ that 从句. eg: I’m sure of the key to the question. 我对这个问题的答案有把握 辨析:be sure of doing sth.与 be sure to do sth. be sure of doing sth. 是对自己而言,而be sure to do sth.则是对别人或其他物而言,除非是祈使句. eg: They are sure of winning the match. (是他们自己有信心) They are sure to win the match. (别人对他们有信心) Language notes iv