Presentation
1) 教学By the time I got outside, the bus had already left. When I got to school, I realized I had left my backpack at home.
Presentation and practice.
T: Now Let’s know something about Mary’s bad day. Please look at the pictures, and tell me something about the pictures.
When she got to school, the bell had rung.
By the time she walked into the class, her teacher had started teaching.
When she got home, she found she had left her keys in the backpack.
When she ran to school, she realized she had left her backpack at home.
2) 教学 结对练习句型
让学生根据1a的图片造句。注意强调过去完成时的结构和用法：
had + p.p.
3) 教学 操练1a, 1c, 2c
让学生根据1a,2a图片内容讲述一个完整的故事，引出get outside, get to school, by the time, start doing, be late for,并用刚刚学到的目标句型来操练。抽查几对学生，让他们在全班面前，按要求进行描述。
4) 教学1b, 2a, 2b
首先，帮助学生明确本题的要求。接着，听力练习，学生根据录音内容完成1b, 2a and 2b.
最后，重放一遍录音内容，学生跟读。