Unit4 Section A不要在上吃东西。_______________________________________________点拨：祈使句是用来表示请求,命令,叮嘱,邀请,劝告或祝愿等的句子。它的特点是以动词原形开头，末尾可用句号或感叹号。祈使句一般只有肯定和否定两种形式。肯定句否定句Please + 动词________ + 其他Please come in.Please + ________+动词________+ 其他Please don’t come in.动词原形 + 其他Open the door !Don’t + 动词原形 + 其他Don’t open the door !Be + 形容词Be quiet !Don’t + be + 形容词Don’t be quiet !Let sb. do sth.Let me do it.Let sb. do sth.Don’t let me do it.Let me not do it.No + 名词/动名词No photos/ parking!不准上课迟到。你必须准时。__________________________________________点拨1：“做某事迟到” _____________________=_____________________点拨2：must是情态动词，强调主观必须。肯定式：must + V原 eg：You must go home now.否定式：must + not + V原或needn’t + V原 eg：You mustn’t smoke here.疑问式：Must + 主语…? eg: Must I do homework now? Yes, you must. No, you needn’t.由must引起的疑问句,肯定回答要用_______________或have to,否定回答要用_______________或don’t have to,意思是“不必”.不准在走廊里跑。__________________________________________________不准在教室里吃东西。你必须在餐厅吃饭。_____________________________________________________________________不准在上听音乐。_______________________________________________不准打架。这 |
