单项选择题
A. 8 days. B. 2 days. C. 4 days. D. 2 weeks.
A. to write in an amusing way B. to give general advice C. to complain about his health D. to describe personal experiences
A. the ground where birds like to live B. the place where birds usually live C. the tree-tops, the air and the water D. rules that hold true for most birds