Unit 10I’ve had this bike for three years.Present perfect tense with since and for Grammar Lesson: for and since1. 现在完成时表示动作或状态在过去已经 开始，持续到现在可能还要持续下去， 常和 for, since 引导的表示一段时间的时 间状语连用，谓语动词多用延续性动词。如： live, teach, learn, work, study, be open, be closed, keep, have, be away, be married, be asleep, be ill 等。如： for twenty-three yearsI have worked here since 1991. since twenty-three years ago自从 1991 年以来我就在这儿工作。We have learned English for three years. since three years ago我们学英语 3 年了。 注意： 1 ） since + 时间点， for + 时间段， 如： since last week, for two days 。since 2012我买了这辆自行车三年了We have had this bike for three years.since three years agoFill in the blanks.1. — How long have you lived here? — I’ve lived here ____ twenty years. 2. Yes, I’ve been here _____ 1976.3. We haven’t seen each other ______ last week. 4. My parents and I have been in Hong Kong ____ two days. forsincesincefor5.Jeff has had his bike ____ more than 10 years.for6.Amy has had the toy bear ______ she was a baby.since7.Amy has had her favorite book ____three years ago.since2. 短暂性动词 (come, go, leave, buy …)可 以用于现在完成时。但不能用于带有 for 或是 since 的肯定句中。He has left Beijing for a week.He has not left Beijing yet. (×)(√)3. 短暂性动词变为延续性动词的现在完成 时构成举例：buy have / has hadborrow have / has keptarrive have / has been in / atleave have / has been awayopen have / has been openclose have / has been closedjoin have / has been in have / has been a member ofdie have / has been deadmarry have / has been marriedcome / go have / has been in / atbegin / start have / has been onfinish / stop have / has bee...
