肯定句变否定句专题 详细版课件

1、肯定句变否定句专题一、有be动词或情态动词：有be动词（am/is/are）或者情态动词（can/must/may/will/could/would/should）的句子，一般直接在be动词或情态动词后面加“not”。 例如： She is not a teacher.I am a student. I am not a student. They are workers They are not workers. She is a teacher. I can run fast. I can not run fast. She will go to school tomorrow. She

2、will not go to school tomorrow. You should do your homework. You should not do your homework. 二、句子动词为实意动词的情况： 主语为三人称单数，在主语后面加上doesnt,动词变回原形.如：He likes Chinese food. He doesnt like Chinese food. She has a round face. She doesnt have a round face. 2、主语不是三人称单数，在主语后面加dont,其他不变。如：We go to school together

3、. We dont go to school together. They want to play basketball. They dont want to play basketball. 三、祈使句变否定句祈使句：表示请求、命令等的句子叫祈使句。它的主语是听话人(you) ，一般不需要说出来。通常以动词原形开头。如：Open the door, please. 请把门打开。 Be quiet, boys. 孩子们，安静点。 Hurry up!快点跟上 1.一般说来，祈使句的否定是在祈使句首加Dont。如 Come here. Dont come here. Listen to the

4、teacher carefully. Dont listen to the teacher carefully. Be angry. Dont be angry. 2.let型当祈使句表示邀请或建议(Lets) 时，则在Let后面加not。如： Lets talk about it. Lets not talk about it. Lets go swimming there. Lets not go swimming there. 特殊：1.some变为any。如： There are some birds in the tree. There arent any birds in the

5、tree. 但是，若在表示请邀请、请求的句子中，some可以不变。如： I would like some orange juice. Would you like some orange juice? 与此相关的一些不定代词如something, somebody等也要进行相应变化。 2.and变为or。如： I have a knife and a ruler. I dont have a knife or a ruler. 3.a lot of (=lots of)变为many或much。如： They have a lot of friends.（可数名词）They dont have

6、 many friends. There is lots of orange in the bottle.（不可数名词） There isnt much orange in the bottle. 4.too变为either 如：She is Chinese. He is Chinese too. She is not Chinese. He is not Chinese either. 练习：I am a student.I like vegetables.I have an aunt.I can play football.I prefer ice-cream and Coke.He is from England.They are doing their homework.We go to school together.There is a new bed in the bedroom.There are some birds in the tree.Listen to me carefully.Lets make a card for