A：草原、荒漠、森林
B：温带草原、荒漠草原、荒漠
C：森林、荒漠、草原
D：荒漠、森林、草原
—____ ( What time / When ) do you have a football class?
—On Tuesdays.
分解因式：2x2﹣4x=____．
My brother_____while he_______ his bike and hurt himself.
