北师大初中英语九上《Unit 4 Inventions and Inventors》PPT课件 (1).ppt

1、Unit 4 Inventions and Inventors,一、本周教学重点： 1. 复习被动语态 2. 情态动词表达怀疑、确定和可能。 3. 重点词汇,二、具体内容： （一）被动语态： 1. 一般现在时被动语态基本结构： 主语am/is/are过去分词 The food is placed in the oven. They are turned into heat.,2. 一般过去时被动语态基本结构： 主语was/were过去分词 Magic Squares were invented in China. Papermaking was introduced into Japan in

2、 610. 3. 情态动词被动语态基本结构： 主语can/should/mustbe过去分词 School uniform must be worn at all times.,4. 一般将来时被动语态基本结构： 主语willbe过去分词 It cant be a radio because its too big to be a radio. The report will _ （finish）in two days time. Milk should _ （keep）in the fridge. White clothes and colored clothes should not _（

3、wash）together. School uniforms neednt _（wear）at all times.,（二）情态动词： 当不是很确定时，用might或may. （might比may更不确定） Who knows what will happen. You may even have married by then. It might be a tool for cutting things. I dont know. 当确定某件事是唯一的可能时，用must. It must be some sort of toy. 当确信不可能发生时，用cannot. It cannot be

4、 a radio because its too big to be a radio.,Ex. Complete the sentences with might be / may be, cannot be, or must be. 1. This exam _ too difficult for the students. I dont think they can finish it. 2. It _ a book for children. There are many cartoons in it. 3. It _ true. I think you made a mistake.

5、4. Mr. Smith _ in London, Paris, or Tokyo. No one knows for sure. 5. That _ John. He is in New York now. 6. Did you hear the doorbell? It _ Nicholas. I am expecting him.,（三）重点词汇： 1. In many big cities in the world, the overuse of cars is thought to be one of the major causes of air pollution. over名词

6、/形容词，表示“过多，过于” The over-load truck caused a serious road accident. She always works overtime, so she has to leave her baby cared for by her mother. be thought to be 被认为，被看作 She is thought to be the top student in our class. Jane is thought to be busy preparing for the exam.,2. However we are also wa

7、rned not to ask for pretty colors, because the car will come in gray only. warn No one warned him of the danger. I warned her not to get close to the dog but she wouldnt hear of it.,3. Other experts are sure that the future will be happy. be sure that I am sure that smoking will hurt you. Are you su

8、re that John will come this afternoon? 4. If gas is in short supply, the super car will run on water. be in short The cheaper it is, the better. Im short of money. on 靠 He finds it difficult to live on his salary. They live mostly on vegetables from their garden.,5. As a rule, soft fruits like straw

9、berries, etc, are difficult to freeze. as a rule 一般来说，通常是 As a rule, she goes out early every evening looking for work. As a rule, we get home at 6.,6. You should be careful the first time you wash your shirt because the blue color might come out and mark the white part. come out 开花，出版，退色，计算出来 This

10、magazine comes out monthly. Some flowers have begun to come out. I washed the shirt twice but the ink still hasnt come out. 7. observe 观察 I observed a letter on the table. Did you observe anything strange in that boys behavior?,Exercise,课堂练习 I. 单选。 1. Have you ever this kind of moon cakes? A. eat B.

11、 eats C. eating D. eaten 2. The knives are used cutting things. A. in B. to C. for D. of 3. They are used for the style of a shoe. A. change B. changes C. changing D. changed,4. Must I stay at home, Mum? - No, you . A. neednt B. mustnt C. dont D. may not 5. She asked them things about. A. not to lit

12、ter B. dont litter C. not litter D. no litter 6. Im not sure he will come back home tomorrow or not. A. when B. what C. whether D. where,7. Look. These be dinosaur eggs because they are the biggest of all. A. must B. can C. should D. may 8. I was told to take umbrella with me. -Oh, no. look at the s

13、ky. Its sunny and rain. A. must B. cant C. may D. neednt 9. The light in the office is off. The teacher be there now. A. may B. cant C. mustnt D. must,II. 完成句子： 1. 警察阻止孩子们在街上玩耍。 The policeman stopped the children in the street. 2. 去年他去日本学医。 Last year, he went to Japan . 3. 她每天早起以便能读英语。 She gets up early every day she can read English.,III. 连词成句 1. The money/ count/ every evening _ 2. The children/ take care of /in the kindergarten _ 3. English/ speak/ everywhere _,Thank you!Bye!,