初中英语考试必考语法:初中英语八大时态
2019-01-17 13:59
来源:常熟星火教育
作者:
现在完成时
1. 概念:过去发生或已经完成的动作对现在造成的影响或结果,或从过去已经开始,持续到现在并且有可能继续下去的动作或状态。
2. 时间状语:recently, lately, since, for, in the past few years, etc.
3. 基本结构:have/has + done 否定形式:have/has + not +done. 一般疑问句:have或has。
4. since的三种用法
(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. 1989起,我一直在这儿。
(2)since +一段时间+ ago。I have been here since five months ago. 我在这儿,已经有五个月了。
(3)since +从句(一般过去时)。Great changes have taken place since you left. 你走后,变化可大了。比较since和forsince 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.我住在这儿二十多年了。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。)
过去完成时
1. 概念:以过去某个时间为标准,在此以前发生的动作或行为,或在过去某动作之前完成的行为,即“过去的过去”。
2. 时间状语:before, by the end of last year(term, month),etc.
3. 基本结构:had + done. 否定形式:had + not + done. 一般疑问句:had放于句首。
4. 用法
(1)在told, said, knew, heard, thought等动词后的宾语从句种。例如:She said (that)she had never been to Paris. 她告诉我她曾去过巴黎。
(2)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。例如:When the police arrived, the thieves had run away. 警察到达时,小偷们早就跑了。
(3)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…,未能…"。例如:We had hoped that you would come, but you didn't. 那时我们希望你能来,但是你没有来。注意:
had hardly… when... 刚......就......。例如:I had hardly opened the door when I he hit me. 我刚打开门,他就打了我。had no sooner…than 刚…… 就……。例如:He had no sooner bought the car than he sold it. 他刚买了这辆车,转眼又卖了。