根据句意和所给的中文提示，写出句子中的单词。
Could you please tell us about the four great____ (发明) of China?21世纪教育网
He’s already____ (喂养) his pet dog.
My grandfather is interested in____ (收集) old coins.
The dentist suggests that we should brush____ (牙齿) three times a day.
After the sudden earthquake, most of us were____ (醒着) all the night.
