徐州成人英语培训班机构中心经典学习资料.doc

徐州成人英语培训班机构中心经典学习资料语法是掌握英语的一个基础，打好这个基础会使你分析文章更容易，也能够写出很好的句式since的四种用法1) since +过去一个时间点(如具体的年、月、日期、钟点、1980, last month, half past six)。I have been here since 1989.2) since +一段时间+ agoI have been here since five months ago.3) since +从句Great changes have taken place since you left.4) It is +一段时间+ since从句It is two years since I became a postgraduate student.延续动词与瞬间动词1) 用于完成时的区别延续动词表示经验、经历； 瞬间动词表示行为的结 果，不能与表示段的时间状语连用。 He has completed the work.他已完成了那项工作。 (表结果) Ive known him since then. 我从那时起就认识他了。(表经历)2)用于till / until从句的差异 延续动词用于肯定句，表示做直到 瞬间动词用于否定句，表示到，才 He didnt come back until ten oclock.他到10 点才回来。 He slept until ten oclock.他一直睡到10点。典型例题1. You dont need to describe her. I _ her several times.A. had metB. have met C. metD. meet 答案B. 首先本题后句强调对现在的影响，我知道她的模样，你不用描述。再次，several times告知为反复发生的动作，因此用现在完成时。2.-Im sorry to keep you waiting.-Oh, not at all. I _ here only a few minutes.A. have been B. had been C. wasD. will be 答案A. 等待的动作由过去开始，持续到现在，应用现在完成时。（四）过去完成时1） 概念：表示过去的过去其构成是had +过去分词构成2） 用法a.在told, said, knew, heard, thought等动词后的宾语从句。 She said (that) she had never been to Paris.b. 状语从句 在过去不同时间发生的两个动作中，发生在先，用过去完成时；发生在后，用一般过去时。 When the police arrived, the thieves had run away.3)过去完成时的时间状语before, by, until , when, after, once, as soon as。 He said that he had learned some English before. By the time he was twelve, Edison had began to make a living by himself.Tom was disappointed that most of the guests had left when he arrived at the party.典型例题 The students _ busily when Miss Brown went to get a book she _ in the office.A. had written, leftB，were writing, has left C. had written, had leftD. were writing, had left 答案D. 把书忘在办公室发生在去取书这一过去的动作之前，因此忘了书这一动作发生在过去的过去，用过去完成时。句中when表示的是时间的一点，表示在同学们正忙于这一背景下，when所引导的动作发生。因此注意：had no when还没等 就had no sooner than刚 就 He had no sooner bought the car than he sold it.过去完成时与现在完成时的比较I have known him for three years.我认识他三年了。I had known him when I was a student.我当学生时，就已经认识他了。过去完成时与现在完成时二者用法基本相同，但现在完成时以现在的时间为基点，过去完成时则以过去的时间为基点，与现在无关，即过去的过去。I have finished my experiment.我已经做完实验了。（表示现在说