问题
选择题
— Have you seen Mr. Smith?
— He arrived ______ you were asleep. [ ]
A. since
B. while
C. before
D. until
答案
答案：B
搜题请搜索小程序“爱下问搜题”
— Have you seen Mr. Smith?
— He arrived ______ you were asleep. [ ]
A. since
B. while
C. before
D. until
答案：B
