助动词的用法精要.pptx

助动词的用法 授课人：杨琳 ★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. What’s the function of the underlined words? 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 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。 帮助主要动词构成虚拟语气 ★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. What’s the function of “do/did”? 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