如图,在△ABC中,△ADE的周长为8,DH为AB的中垂线,EF垂直平分AC,则BC的长为( )
A:4
B:6
C:8
D:16
理解课文《去打开大自然绿色的课本》,回答下面两个问题
( )
若菱形的两条对角线长分别是6和8,则此菱形的周长是____ ,面积是____
It's said ________ a little child does ________ much homework every day.
当你有想不通的事时,你应该( )