根据句意,补全单词.

1. We can't find the good             to show our thankful to you for giving us so much help.

2. Some germs are very ___   _, so we must see them with the microscope.

3. Many people think it is not good to keep the wild animals in the    ____.

4. Don't forget to ____    the dog or he may be hungry.

5. A lot of parents _     __ the government to care for teenagers getting online through their mobile phone.

船舶常用的电力变压器从冷却的方式上看，属于（）。

A．强迫风冷

B．水冷

C．油浸变压器

D．自然风冷