问题补充:
--- will your head teacher return from the USA?
---In two days.
A. How long
B. How soon
C. How often
D. How old
答案:
A. How long
(答案→)B. How soon
C. How often
D. How old
解析:此题答案错误,短语辨析。How long 多长时间,How soon 多久,表示将来How often 表示频率,多久一次,How old 多大,in +时间表示将来,常用来回答以how soon提问的特殊疑问句。所以选B。