问题
选择题
I didn't hear the phone. I _____ asleep. [ ]
A. can be
B. must have been
C. must be
D. should have been
答案
答案：B
搜题请搜索小程序“爱下问搜题”
I didn't hear the phone. I _____ asleep. [ ]
A. can be
B. must have been
C. must be
D. should have been
答案：B