语法百科全书(编辑修改稿)

语法百科全书(编辑修改稿)内容摘要：

town at all? No, this is the first time I ___ here. A. was B. have been C. came D. am ing 答案 B. This is the first time 后面所加从句应为现在完成时，故选 B。 (2) Have you ____ been to our town before? No, it39。 s the first time I ___ here. A. even, e B. even, have e C. ever, e D. ever, have e 答案 D. ever 意为曾经或无论何时，反意词为 never，此两词常用于完成时。 This is the largest fish I have ever seen. It is / was the first time +thatclause 的句型中，从句要用完成时。 注意：非延续性动词的否定形式可以与表示延续时间的状语连用。 即动作不发生的状态是可以持续的。 （错） I have received his letter for a month. （对） I haven39。 t received his letter for almost a month. 比较 since 和 for 中国最庞大的实用下载资料库 (负责整理 . 版权归原作者所有 ) Since 用来说明动作起始时间， for用来说明动作延续时间长度。 I have lived here for more than twenty years. I have lived here since I was born.. My aunt has worked in a clinic since 1949. Some new oilfields have been opened up since 1976. I have known Xiao Li since she was a little girl. My brother has been in the Youth League for two years. I have not heard from my uncle for a long time. 注意：并非有 for 作为时间状语的句子都用现在完成时。 I worked here for more than twenty years. (我现在已不在这里工作。 ) I have worked here for many years. (现在我仍在这里工作。 ) 小窍门： 当现在完成时 +一段时间，这一结构中，我们用下面的公式转化，很容易就能排除非延续动词在完成时中的误使。 1) (对 ) Tom has studied Russian for three years. = Tom began to study Russian three years ago, and is 中国最庞大的实用下载资料库 (负责整理 . 版权归原作者所有 ) still studying it now. 2) (错 ) Harry has got married for six years. = Harry began to get married six years ago, and is still getting married now. 显然，第二句不对，它应改为 Harry got married six years ago. 或 Harry has been married for six years. 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 + ago I have been here since five months ago. 3) since +从句 Great changes have taken place since you left. Considerable time has elapsed since we have been here. 中国最庞大的实用下载资料库 (负责整理 . 版权归原作者所有 ) 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 pleted the work. 他已完成了那项工作。 (表结果 ) I39。 ve 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 didn39。 t e back until ten o39。 clock. 他到 10 点才回来。 He slept until ten o39。 clock. 他一直睡到 10 点。 典型例题 中国最庞大的实用下载资料库 (负责整理 . 版权归原作者所有 ) 1. You don39。 t need to describe her. I ___ her several times. A. had met B. have met C. met D. 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。 39。 m sorry to keep you waiting. Oh, not at all. I ___ here only a few minutes. A. have been B. had been C. was D. 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。 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。 那时以前 那时 现在 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； 中国最庞大的实用下载资料库 (负责整理 . 版权归原作者所有 ) 发生在后，用一般过去时。 When the police arrived, the thieves had run away. c. 表示意向的动词，如 hope, wish, expect, think, intend, mean, suppose 等，用过去完成时表示 原本。