Unit 3 The Internet Discovering Useful Structures 课件-2023-2024学年高中英语人教版（2019）必修第二册

Unit 3 The Internet Grammar By Ellen present(now) future past 过去的动作一直持续到现在 过去的动作对现在产生影响 The Present Perfect Tense I have lived in China for 5 years. 我在中国住了5年。（从5年前到现在，现在还在中国） I lived in China for 5 years. 我在中国住了5年。（过去住在中国，现在不在中国） 过去的动作一直持续到现在 过去的动作对现在产生影响 Someone has broken the window. (窗户现在是坏的) I have already lost the key. (我现在没有钥匙) I haven't read the book yet. (不了解书的内容) 肯定式： S+have/has+V-过去分词(done) 否定式： S+have/has+not+V-过去分词... 一般问句： Have/Has+S+V-过去分词... 特殊疑问句： 疑问词+have/has+S+V-过去分词... 现在完成时的基本结构 “三变” 例：They have already solved the problem. 原句主语 by的宾语 宾语 主语 谓语由主动 被动 “三不变” 原句意思不变 原句时态不变 原句主谓宾以外成分不变 The problem ________________________ by them. has aalready been solved 被动语态 肯定式： S+have/has been done... 否定式： S+have/has not been done... 一般问句： Have/Has+S+been done 特殊疑问句： 疑问词+have/has+S+been done 现在完成被动语态的基本结构 练习 Tom has invited the singer already. The singer has been invited (by Tom) already. The singer has not been invited (by Tom) yet. Has the singer been invited (by Tom) yet ? Who has been invited (by Tom) ? 被动 否定 一般疑问 对宾语提问 [即时演练1]——用现在完成时的被动语态改写句子 (1)Jack's boss has always praised him for his devotion to work. →Jack ________________________by his boss for his devotion to work. (2)They have found a good place to build a temple in the village. →A good place ____________________by them to build a temple in the village. (3)We haven't yet decided how to solve that difficult technological problem. →How to solve that difficult technological problem ____________________ by us yet. has always been praised has been found hasn't been decided 三、用法 1．表示被动的动作在说话之前已经完成，强调过去的动作对现在造成的影响或产生的结果，通常与already、yet、never、recently等副词及时间状语so far、by now、up till/to now、since等连用。 ◆The database has already been updated. 数据库已经被更新了。(现在可以使用新的数据库了) 2．表示一个被动的动作或状态从过去开始一直持续到现在，并可能继续持续下去，常与for或since等引出的时间状语(从句)连用，或用于how long引出的句子中。 ◆The machine has been repaired for two hours. 这台机器已经被修了两