一道初中定语从句题

问题描述:

一道初中定语从句题
The freezing point is the temperature __________ water changes into ice.
再加一道The reason is __________ he is unable to operate the machine.

The freezing point is the temperature at which water changes into ice.凝固点就是水变成冰的温度. which 指代temperature.意思是在这个温度水变成了冰.The reason is that he is unable to operate the machine....