进入教室的送风道的主断面尺寸 (高×宽)宜为( )。
A.300×600
B.550×1000
C.600×950
D.700×800
参考答案:B
A few minutes earlier, and you would have seen the NBA star. But you ________.
A.won't come
B.don't come
C.didn't come
D.haven't come
三条或三条以上的发育沟相交所形成的凹陷称为
A.窝
B.点隙
C.外展隙
D.楔状隙
E.邻间隙