风管板材拼接时，咬接不得有十字交叉缝，但焊接可有。( )
参考答案：错
已知函数y=（m+2）xm（m+1）是二次函数，则m=( )．
— ____ do you watch TV every week ?
一Less than two hours I often have much homework to do. [ ]
A.How many
B.How much
C.How long
D．How often
