问题补充:
---do you spend _English learning every day? ---For about an hour.
A. How long, in
B. How many times, on
C. How often, on
D. How long, on
答案:
A. How long, in
B. How many times, on
C. How often, on
(答案→)D. How long, on
解析:For+ 一段时间,用How long提问,spend + 时间 + on +名词,题中English为名词,所以选D。