UNIT 9 Section Ⅲ GRAMMAR（Word教参）-【优化指导】2022-2023学年新教材高中英语选择性必修第三册（北师大版2019）

Section Ⅲ　GRAMMAR 完成时 [对应学生用书P124] [观察] 1．We have received no news from her since she left here. 2．I have seen him only once this year. 3．I'll not believe you unless I have seen it with my own eyes. 4．He had been waiting for two weeks.He was still waiting. [归纳] 完成时表示一个完成的动作。用来表示现在、过去或者将来的某个时间点已经或将会完成的动作。 [对应学生用书P124] 1．构成：主动式：have/has done；被动式：have/has been done。 2．用法： (1)现在完成时表示从过去持续到现在的动作或状态。现在完成时的这种用法通常与由since或for引导的时间状语连用。例如： The old man has lived here for more than twenty years. 这个老人已在此处住了二十多年了。 (2)现在完成时表示过去发生的但对现在有影响的动作。 ①现在完成时的这种用法有时不带时间状语，有时可以和already，before，ever，just，lately，never，once，recently，yet等一些所指时间不具体的时间状语连用。例如： Have you ever been to Australia? 你去过澳大利亚吗？ I have already finished the work. 我已经干完活了。 ②有时现在完成时和now，today，this morning，this week，this year等表示现在的时间状语连用。 I haven't seen him today. 我今天没见过他。 (3)现在完成时在时间和条件状语从句中表示将来完成的动作。 I'll go to the party as soon as I have finished my homework. 我一完成作业就会去参加聚会。 (4)现在完成时和until now，so far，in the past few years，up to the present等表示从某时到目前这段时间的状语连用。例如： I have not heard from her so far. 到目前为止，我没有收到过她的信。 We have learned five hundred words up to the present. 到目前为止，我们已学了五百个单词。 (5)在“最高级＋名词”或“It/This is/will be＋the first/second ...time”之后的定语从句中，谓语动词用现在完成时。例如： This is the first time (that) I have come here. 这是我第一次来这里。 It's the best film I have ever seen. 这是我看过的最好的一部电影。 ①当意义明确时，使用现在完成时的句子可以不用时间状语。 He has done a lot of work. 他干了许多工作。 She has told me about her story. 她跟我讲过她的故事。 ②瞬间动词又叫非延续性动词、终止性动词。瞬间动词可以用于完成时态，但不可以接表示一段时间的状语；若要接表示一段时间的状语，需要做一些相应的变换。 He has come to Beijing since last year.(×) He has lived in Beijing since last year.(√) [即学即练]　单句填空 ①The reports went missing in 2021 and nobody has seen(see) them since. ②In the past few years，many new railways have been laid(lay) down. ③We won't start the work until all the preparations have been made(make). 1．构成：have/has been doing 2．用法： (1)表示“持续”：现在完成进行时表示从过去一直持续到现在的动作或刚刚结束的动作。例如： I've been writing letters all this morning. 我写了一上午信。(动作不再继续) O'Nell is ill.He's been lying in the