问题
选择题
You ________ smoke when you see the sign. [ ]
A. must
B. should
C. mustn't
D. needn't
答案
答案：C
搜题请搜索小程序“爱下问搜题”
You ________ smoke when you see the sign. [ ]
A. must
B. should
C. mustn't
D. needn't
答案：C