问题
选择题
—May I smoke here?
—No , you _____. This is a no-smoking room. [ ]
A. needn't
B. couldn't
C. mustn't
D. won't
答案
答案：C
搜题请搜索小程序“爱下问搜题”
—May I smoke here?
—No , you _____. This is a no-smoking room. [ ]
A. needn't
B. couldn't
C. mustn't
D. won't
答案：C
的电池两端，则电学元件两端的电压是 V．