用电安全应做到：在移动带电设备时，必须先（），并保护好导线，以免磨损或拉断。
参考答案：切断电源
改写句子。
1. We have to stay in the classroom to wait for our teacher. (对划线部分提问).
_____ _____ you _____ _____ _____?
2. They are busy studying for the test. (对划线部分提问)
_____ _____ they busy _____?
3. Do you want to join us?
_____ you _____ _____ _____ us?
形成性评价
