助动词的用法.pptx

助动词的用法授课人：杨琳What’s the function of the underlined words? ★We are having an English class. ★ I have seen the film. ★ He didn’t go home last night. ★ We will fly for Africa next month. 帮助主要动词have构成现在进行时帮助主要动词see构成现在完成时帮助主要动词go构成一般过去时帮助主要动词fly构成一般将来时What’s the function of the underlined words?★ He was sent to England. ★I would fly to Sweden if I were a bird.★Had I lived in London, I would have been to London Bridge.帮助主要动词send构成被动语态帮助主要动词构成虚拟语气帮助主要动词构成虚拟语气1 助动词和其他动词一起构成时态、语气和语态。可以用作助动词的有be、do、have和情态动词。What’s the function of “do/did”?★Do you like college life?★ Did you study English before you came here?★ I do not like him.★ Do call me tomorrow. ★He did know that.构成疑问句构成疑问句构成否定句构成强调结构构成强调结构助动词还可用来构成否定或疑问句，以及强调结构。总结：助动词是帮助主要动词构成各种时态,语态,语气以及否定或疑问结构的动词.助动词分为时态助动词和结构助动词两种1. 助动词be的用法1） be +现在分词，构成进行时态They are having a meeting.　他们正在开会。English is becoming more and more important. 英语现在越来越重要。2）be + 过去分词，构成被动语态。The window was broken by Tom..　窗户是汤姆打碎的。English is taught throughout the world.　世界各地都教英语。3） be + 动词不定式，可表示下列内容：a. 表示最近、未来的计划或安排。 He is to go to New York next week..　他下周要去纽约。We are to teach the freshmen.　我们要教新生。b. 表示命令You are to explain this.　对此你要做出解He is to come to the office this afternoon.　要他今天下午来办公室。c.　征求意见How am I to answer him?　我该怎样答复他？Who is to go there?　谁该去那儿呢？d. 表示相约、商定We are to meet at the school gate at seven tomorrow morning.　我们明天早晨7点在校门口集合。2. 助动词have的用法1）have +过去分词，构成完成时态。He has left for London.　他已去了伦敦。By the end of last month, they had finished half of their work. 上月未为止，他们已经完成工作的一半。2）have + been +现在分词，构成完成进行时I have been studying English for ten years. 我一直在学英语，已达十年之久。3）have +been +过去分词，构成完成式被动语态。English has been taught in China for many years. 中国教英语已经多年。3.助动词do 的用法1）构成一般疑问句。 Do you want to pass the CET?　你想通过大学英语测试吗？Did you study German?　你们学过德语吗？2）do + not 构成否定句。I do not want to be criticized. 我不想挨批评He doesnt like to study. 他不想学习。In the past, many students did not know the importance of English.3） 构成否定祈使句。Dont be so absent-minded.不要这么心不在焉说明： 构成否定祈使句只用do，不用did和do