七年级英语下册 Unit 4 Don’t eat in class语法专练练习 （新版）人教新目标版.doc

Unit 4 Dont eat in class单元语法专练祈使句1.定义:用来表达命令、请求、劝告、警告、禁止等的句子叫作祈使句。祈使句通常省略主语you。例如:Be quiet,please.请安静。Please have a seat.请坐。2.句式结构:(1)Do型:动词原形+宾语+其他。例如:Go this way,please.请这边走。(2)Be型:Be+表语+其他。例如:Be a good kid!要做一个好孩子!(3)Let型:Let+宾语+动词原形+其他。例如:Let me help you.让我来帮你。注意:祈使句的否定形式一般都是在句首加Dont构成,有时也直接可用No开头表示禁止。例如:Dont be late for school!上学不要迟到!No smoking!禁止吸烟!haveto与must的用法have to和must均可表示“必须”。must更加强调说话者的主观意愿,而have to强调客观的必要性,意为“不得不”。两者的否定式含义大不相同。mustnt表示“不准;禁止”,而dont have to 表示“不必”。例如:I must go now,or Ill be late.我现在必须走了,否则就会迟到了。She has to help her mother look after her sister.她不得不帮着她妈妈照顾她妹妹。You mustnt swim in the river.你不准在河里游泳。You dont have to do it now.你现在不必做它。注意:以must开头的一般疑问句,其肯定回答用must,否定回答用neednt或dont have to。例如:Must I finish the work now?我现在必须完成这项工作吗?Yes,you must./No,you dont have to.是的,你必须完成。/不,你不必完成。.根据句意用所给词的适当形式填空1.Do(do) the work right now(立刻),Jim.2.Pleasetell(tell) me the news.3.Letsplay(play) soccer now.4.You mustcome(come) to school on time.5.Dont let(not let) the dog come in.根据句意用must或haveto的适当形式填空1.Youmustdo it yourself.2.MustI read the book in the reading room?No,youdont have to.3.Its late.Jimhas togo home.4.MustLily keep quiet?Yes,shemust.5.You donthave toget up early on weekends.按要求完成句子,每空一词1.You cant listen to music when your mother is sleeping.(改为祈使句)Dontlistento music when your mother is sleeping.2.He has to be in bed by ten oclock.(改为一般疑问句)Doeshehaveto be in bed by ten oclock?3.You must come here early this afternoon.(改为祈使句)Comehere early this afternoon.4.Let her help you.(改为否定句)Dontlether help you.5.She has to listen to the teacher