1，Turn off the switch when anything goes wrong with the machine. 当机器出了故障就把开关关闭。
2，When there is no gravity, our feet can no longer stay on the ground. 没有了重力我们的双脚就无法站立在地面上。
3，Mother arrive home when I am doing my homework. 妈妈到家时我正在做作业。
4，When I was going to have a bath, the phone rang. 我正准备去洗澡时电话响了。
5，When he had finished his homework，he took a short rest. 他完成所有的家庭作业后可以休息一小会。
6，When I got to the airport, the guests had left．当我赶到机场时，客人已经离开了。
7，When we were dancing, a stanger come in. 我们在跳舞时，一个陌生人进来了。
8，When she was making a phonecall，I was writing a letter．她打电话时我正在写信。
9，You shall borrow the book when I have finished reading it. 等我把书看完你可以来借阅。
10，When the manager comes here for a visit next week, I'll talk with him about this．当经理下周来这参观时，我会跟他谈论这个问题。
11，I'll ask her when she comes. 等她来了我会问她的。
12，I will tell him about it when I see him. 等我看到他了我会告诉他。
13，When you start the engine, you must see to it that car is in neutral. 开启发动机时要保证汽车的离合器处于空档的位置。
14，I'll tell him about it when he comes. 等他来了我会告诉他。
