1、Module 5 Museums模块语法小专题语法精讲一、表禁止的多种结构1 “No名词/动名词”可以构成禁止性的警示语，常用来表达“禁止做某事” ，其后不可接宾语。如：No smoking！禁止吸烟！No parking！禁止停车！2否定的祈使句同样可以用来表示“禁止；不要” 。如：Dont shout.不要喊叫。Dont run in the street.不要在街道上跑。3肯定的祈使句也可表“禁止” ，但要靠谓语动词来表示。如：Stop talking！不准说话！4情态动词 mustnt 也可表“禁止” 。如：You mustnt tell it to anyone.你绝不可以告诉任何人
2、。You mustnt come to school late.你上学绝对不能迟到。5cant 可以表示“不能，不会” ，也可以表示“不允许” ，可以用来表示“制止某人做某事” 。如：You cant speak loudly here.你不能在此大声讲话。You cant eat in class.你不能在课堂上吃东西。6You arent allowed to (do)句型也可以用来表示制止对方做某事。如：You are not allowed to park here.你不被允许在这里停车。He isnt allowed to play computer games any more.他
3、再也不被允许玩电脑游戏了。二、if 从句：if 从句祈使句“if 从句祈使句”相当于汉语的“如果就” 。1if 从句的构成先来看几个例子：If you want to go，please tell me.如果你想去的话，请告诉我一声。If you want to know more about it，call now.如果你想了解更多内容，现在就打电话吧。If you want to know what to see，look at the guide.如果你想知道有什么可看的，就看看指南吧。从例句中可以看出，if 后面要接一个完整的句子作从句。2if 从句的位置if 引导的从句可放在主句之前
4、，也可以放在主句之后。如：If you ever go to London，make sure you visit the Science Museum.如果你去伦敦，一定要去参观科学博物馆。这个句子可以改写为：Make sure you visit the Science Museum if you ever go to London.3if 从句的用法“if 从句祈使句”这种结构主要用来表示建议。比如说，有人生病了，你建议他去看医生，可以说：If you dont feel well，please go to see the doctor.如果你不舒服，就去看医生吧。语法精练.用括号内所给
5、单词的适当形式填空。1Dont_be(not be) late.2No eating(eat) here.3Dont_speak(not，speak) with your mouth full of food.4No_talking(no，talk) or reading(read) a book.5You arent allowed to_drop(drop) litter in the park，Sam.6Look(look) out！A car is coming.7If you want to go with me，get(get) up earlier.8You cant smoke
6、(smoke) in the hospital.9If he breaks(break) the traffic rules，punish him at once.10You mustnt shout(shout) in the classroom.单项选择。(B)11.The doctor says， “_ work so hard.”AStop BDontCCant DNo(B)12.Look at the sign“_ here”ANot photos BNo photosCDont photos DCant photos(A)13.Kate，_ your homework here t
7、omorrow.Abring BbringsCto bring Dbringing(A)14._ careful!ABe BBeingCTo be DTo(D)15._ you want to be better，work harder，please.ABecause BSoCThough DIf.按要求完成句子，每空一词。16Will you please read it again more slowly？(改为祈使句)Read it again more slowly，please.17Please sit next to Nancy.(改为否定句)Dont sit next to Nancy.18Dont fish by the lake.(改为同义句)No fishing by the lake.19You mustnt talk in class.(改为同义句)Dont talk/No_talking in class.20Dont wash your hands！(改为肯定句)Wash your hands！
