My brother works in a hospital ________ our home,so he has to live there.
During the rainy days, I prefer to stay at home ___________ go out.
John ___________ on his friend when he went to Guangzhou last month.
—Paper ___________ wood. We should not waste paper. —I agree. I always use __________ sides of paper.
Are you familiar _____________ the rules of baseball?
In the past, the workers were made __________ 12 hours a day.