家庭电路电压是( )
如图,将下图所示奉为经典的宗教是( )
①对顶角相等;②相等的角是对顶角;③若两个角不相等,则这两个角一定不是对顶角;④若两个角不是对顶角,则这两个角不相等.
We teenagers should the old and offer our seats to them on buses.