— Shall we go for a walk outside? -- ______ .
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.
—Do you like talking with your friends on the telephone or mobile phone?— ___________. I enjoy chatting on line.