1、Unit 12 Life is full of the unexpected.,Section A(1a-2d),任务一,任务二,任务一:观察 对照图片,找出每个句子中发生时间较早的动作。,B,B,B,任务一,任务二,任务二:发现 按照动作发生、发展的先后顺序,晚发生的动作用 时态;早发生的动作结构为 “ ”。 这就是我们本单元要重点学习的过去完成时。,一般过去;had+过去分词,1,2,1.By the time I got up,my brother had already gotten in the shower. 我起床时,我哥哥已经在洗淋浴了。 by the time意为“在以前”,
2、引导时间状语从句,从句用一般过去时,而主句则常用过去完成时。如: By the time Jim came into the classroom,our class had already begun. 吉姆走进教室前,我们已经开始上课了。 By the time I got there,the concert had been on for ten minutes. 我到那儿时,音乐会已经开始十分钟了。,1,2,拓展 by构成的常用短语汇总: by accident/chance 偶然地;意外 by hand用手工(做的);用手 by heart(memory)熟记;背(诵);牢记 by m
3、istake错误地;无心(做了某错事) by oneself 独自地 by the way 顺便问一下 by turns 轮流;交替 drop by顺便访问 little by little一点一点地;逐渐 side by side肩并肩,1,2,2.My alarm clock didnt go off! 我的闹铃没有响! go off在句中意为 “(闹钟) 响”。另外,go off还有“开火;(电灯) 熄灭” 等意思。试比较: The gun went off by accident.枪偶然走火了。 Suddenly the lights went off. 灯突然熄灭了。 拓展 含off的词组还有: set off 出发;开始 put off 推迟;延期 take off 脱下;(飞机) 起飞 get off 下车 hurry off 匆匆离开 turn off 关上;关闭 drop off 放下;下车,