—Must I return the book this week?
— No, you . You can it for 20 days.
A. mustn't: keep
B. needn't; borrow
C. needn't; keep
D. mustn't; borrow
网友回答
A. mustn't: keep
B. needn't; borrow
(答案→)C. needn't; keep
D. mustn't; borrow
解析：mustn't禁止，一定不；needn't不必；keep持有，保存；borrow借来。句意：我必须这周归还这本书吗？——不，你不必。你可以持有20天。结合语境可知选C。