题干
--Dad, can I go to the movies tonight?
--Sure, but you ____ come back home before 9 o’clock.
--Sure, but you ____ come back home before 9 o’clock.
A：ca
B：must
C：may
D：might
答案(点此获取答案解析）
B
表示3abc，“方框”
表示﹣4xywz，则
=