问题
选择题
_________ should not be allowed to go out at night.
A．Twelve-years-old
B．Twelve-year-olds
C．Twelveyearold
D．Twelveyearsolds
答案
答案：B
twelve-year-olds表示一类人,=" twelve-year-old" children
搜题请搜索小程序“爱下问搜题”