教室里投影仪的光源是强光灯泡，发光时必须用风扇给予降温。在使用投影仪时，要求先启动带动风扇的电动机，再使灯泡发光，如果风扇不启动，灯泡就不能发光。下图所示的电路图中能符合要求的是（    ）

根据句意补全单词。

1. Look! Mum is c____________ eggs on the stove.

2. This is the refrigerator. It's c____________ inside.

3. The green toothbrush is mine. The red toothbrush is y____________.

4. My hands are dirty. But your hands are c____________.

5. Today is Sunday. Tomorrow is M____________.