初中英语语法there be句式

基础语法 祈使句 1. 祈使句的意义：表示请求、命令、建议、祝愿、邀请或劝告的句子叫祈使句。2、构成：祈使句通常省略主语，谓语动词用原形。如：1）Shut the door! 把门关上!Have a cup of coffee! 喝杯咖啡吧!2）Be quiet!Be careful！3）Let them go by train. 叫他们坐火车去吧。Let me have a try. 我来试一试。 Lets go home. 咱们回家吧。3）No smoking！ 禁止吸烟。否定式：动词原形前加dont或never；let us/lets+ not + do 如：Open the window. 把窗户打开。Dont open the window. 别把窗户打开。Come next Monday. 下周星期一来。Dont come next Monday. 下周星期一别来。Lets tell him the truth. 我们把实情告诉他吧。Lets not tell him the truth. 我们不要把实情告诉他。无动词祈使句的否定在句首加not。如：Here? Not here. 不是这里。This one? Not this one. 不是这个。3、please的使用：为了使祈使句的语气变得委婉，可以在句首或句末加上please若加在句首，其后不用逗号；若加在句末，则通常会在please前加一个逗号。如：Step this way, please. 请这边走。Please type your letter. 请把你的信打出来。Open the window, please. 请把窗户打开。如果是否定祈使句，则通常将please加在dont之前。如：Please dont get angry. 请不要生气。Please dont telephone before 8 a. m. 早8点以前请不要打电话。4、祈使句的反义疑问句：1) 若陈述部分为祈使句，反意问句通常用will you, wont you等。如：Be careful，will you？Dont go out，will you？Let us go to the museum, will you?若陈述部分为否定式，则反意问句部分只用will you。如：Dont forget to post the letter, will you? 请别忘了寄信。有时根据语境的需要，反意问句也可以用can you, cant you 等：Give me some cigarettes, can you? 给我些香烟，可以吗? Walk faster, cant you? 走快点，不行吗?但是，Lets do, 用shall we? eg. Lets read together, shall we?注意： let us/sb 与 lets 的区别，体会下面几句话：1） Let him in，will you? 请让他进去，好吗？2） Let us go swimming, will you? 请你让我们去游泳，好吗？No, youd better not. 你们最好别去。3） Lets go swimming, shall we? 我们（一起）去游泳，好吗？No, lets not. /Yes, lets. 不要去了。/我们去吧。5、 句型：祈使句+and / then / or+陈述句 这里的祈使句表示条件如：Work hard, and youll pass the exam. 努力点，你会通过考试的。Hurry up, or youll be late.Look through this book and tell me what you think of it. 6、注意区分祈使句和非谓语动词:1）_（get）up early to keep healthy.2) _ （get）up early is good for health.3）_ （catch）the early bus, Mr Smith got up at six.其中，1）题要填Get，前面省略了主语you, 2）题填Getting, 是动名词短语作主语。3)填To catch, 不定式表目的，作目的状语。7、祈使句转化成间接引语：一般借助动词ask, tell, warn, advise, order等。如：“Wake him up,” she said. She told me to wake him up.“Ask your teacher for help,” mother said. Mother advised me to ask the teacher for help. “Carry the box upstairs,” Mr. Brown said to me. Mr. Brown asked me to carry the box upstairs. 拓展知识：1. 祈使句表示强调为了加语气，可在祈使句的动词原形前加上助动词do，此时通常译为“一定”“务必”等。1）. 表示强调的请求。如：Do come with us. 请一定要和我们一起去。Please! Do be quiet a moment! 求求你们! 安静一会儿! Do be careful. 务必要小心。2）. 表示委婉或客气。如：Do try this fish. 请尝尝这鱼。Do have another cup of coffee. 请再喝杯咖啡吧。3）. 表示不耐烦。如：Do stop talking! 别说啦!4）. 希望说服对方。如：Do help me with this maths problem. 务请帮我解答这道数学题。副词never和always有时可用于祈使句句首，表示强调。如：Never do that again. 再不要这样做了。Always look in the mirror before starting to drive. 一定要先看看反光镜再开车。2. 祈使句的时间概念祈使句所表示的时间总是指将来，所以与它连用的句子原则上要用将来时态来与它呼应。如：Give me a hand, will you? 帮我一个忙，好吗?Try again and you will succeed. 你再试就会成功。Dont do that again or youll be in trouble. 别再干那个了，否则你会有麻烦。3. 祈使句的省略一般说来，祈使句总是要以动词原形开头，但是，在某些特殊情况下，我们可以只用一个词或短语来表示祈使句的意义。如：Just a few please. 请给几个就行了。A little more slowly please. 再慢一点。A pound of butter. 给我一磅黄油。Two teas and four coffees, please. 请来两杯茶和四杯咖啡。4. 祈使句的主语：1）有时因为语义的需要，someone, nobody, everybody 等也可用作祈使句主语。如：Nobody say a word! 都不许说话! Someone fetch a pail of water. 谁去打一桶水来。Someone go and see who it is. 谁去看看是什么人来了。Somebody answer the phone please. 请来个人接电话。Everybody sit down and lets have a drink. 大家坐下来喝一杯吧!2）有时用作祈使句主语的还可以特定的某人。如：The boy in the corner come here. 在角落的那个男孩来这里吧! 这类句子有时也可以是否定的。如：Dont anybody get out of here. 大家都别出去! 3）祈使句有时可以保留主语you 第1情况：为了有所区分，祈使句可以保留主语 you。如：You go on; Ill wait. 你们先走，我等着。You wait here for a moment. 你在这儿等一会儿。You girls stand in the front row. 你们女孩子站在前排。You play Romeo and you play Juliet. 你演罗蜜欧，你演朱丽叶。You wait here, Jim, and Mary, you wait there. 你等在这儿，吉姆；玛丽，你等在那儿。第2种情况：为了表示生气或有意表示无礼，祈使句可以保留主语 you。如：You be quiet! 你给我安静! You stop talking. 你给住嘴。You get out of here! 你给我滚出去。You do it right away. 你给我马上就去做。other staff of the Centre. During the war, Zhu was transferred back to Jiangxi, and Director of the new Office in Jingdezhen, Jiangxi Committee Secretary. Starting in 1939 served as recorder of the West North Organization, Secretary of the Special CommitteeAfter the victory of the long March, he has been the