--- Mum I’m going to visit my aunt. What about a week? --- A week is too long. Try to be

问题补充：

--- Mum, I’m going to visit my aunt. What about a week?

--- A week is too long. Try to be back in a of days.

A. number

B. dozen

C. few

D. couple

答案：

A. number

B. dozen

C. few

(答案→)D. couple

解析： a couple of days两三天。