用“who”或“that”填空。

1. The man _______ is talking with my mother is my father.

2. That book is the one _______ I bought yesterday.

3. He is one of the workers _______ have been saved in that accident.

4. They talked of the things and persons ______ they remembered in the factory.

5. All ______ can be done must be done.

我国已成为世界上高铁发展最快，技术最全的国家。在节能技术上，高铁动车组采用了再生制动方式：动车到站前先停止供电，由于______，动车会继续向前运行，电机线圈随车轮转动并在磁场中切割______产生感应电流，将______能转化为电能，自动输入电网。当动车速度减至90km/h以下才进行机械刹车。