高中英语 Itbe＋时间段＋since句型课件高三二轮复习语法专题.ppt

“It be＋时间段＋since ...”句型 * 一、注意四个句型： 1、 It be＋时间段＋since从句 2、 It be ＋时间段＋before从句 3、 It be ＋时间点＋when从句 4、It be＋介词＋时间点/段＋ that从句”为强调句型。 * 二、句型讲解： 1、 It be＋时间段＋since从句。意为“自从……以来已有多长时间了”。 （1）、时态的运用： ①主句中若be为is/has been，since从句用一般过去时； ②若be为was，则从句用过去完成时。 It has been six years since we last saw each other, you know. It has been 20 years since he graduated from the school. It was years since the war had broken out. * (2)、含义理解： It is five years since I studied English. ①当since从句中的动词为“延续性动词”时， 表示否定含义（动作从结束时算起）。 翻译成 “没有干---多久了”。 It is five years since I began to study English. ②当since从句中的动词为“非延续性动词” 时，表示肯定含义（动作从开始时算起）。 翻译成 “干---多久了”。 It is five years since I studied English. * 例如： It is 11 years Hongkong returned to China. It has been five years since she home. It four years since he had died. It two years since he studied English. It is two days she was ill. since left was is since * 2、“It be ＋一段时间＋before从句 （1）、时态的运用： ①主句中若be为一般将来时, 从句用一般现 在时; It will be many years before we meet again. ②若be为一般过去时，则从句用一般过去时。 It was a long time before I got to sleep again. * (2)、句型含义： ① It was ＋时间段＋before ...过了多久… ② It was not ＋时间段＋before ...不久，就… (动作已发生。) 例如： It was several hours?before?I found?it. ① It will be＋时间段＋before 要过多久…才会… ② It will not be ＋时间段＋before 不久…就会…（动作未发生。） 例如：It will be three years before he finishes the work. * 例如： It was two years Macao returned to China. It wont be long before you him again. It long before they escaped from the prison. before see was * 3、“It be ＋时间点＋when从句. 表示“在某时, 做某事”。 （1）、时态的运用：从句中时态与be一致. It+ was+时间点+when-clause ① (be用一般过去时，从句谓语用一般过去时) It+ will be+时间点+when-clause ② (be用一般将来时，从句谓语用一般现在时表将来) It was already evening when he came back. It will be midday when they get home It was 1997 when Hongkong returned to China. * (2)、when在这里引导状语从句，意思是“当----时候”。 It wa