A:walked a crowd of young girl
B:did a crowd of young girls walk
C:were walking a crowd of young girl
D:a crowd of young girls were walking
What time does Jim brush his teeth?
在△ABC中, AB=3,AC=1 ,∠A=30°,则△ABC的面积等于( )
对社会主义社会基本矛盾的认识,错误的是( )