Lesson3 A computer has a keyboard,Learing aims,1.Learn the new words: screen , mouse ,keyboard,2.Learn the sentence:-Does a TV have a screen? -Yes,it does,Iam a cat,Are you a cat,Is this a dog,This is a dog,I can swim,I have a ruler,Do you have a ruler,Can you swim,screen,A TV has a screen,自学提示,1.有be动词的如何变一般疑问句？ 2.有情态动词的如何变一般疑问句？ 3.没有be动词，情态动词，主语不是第三人称单 数怎么变？当主语是第三人称单数又如何变,mouse,Does a TV have a mouse,No,it doesnt,keyboard,Does a TV have a keyboard,No,it doesnt,Does a computer have a screen,Yes,
