A lot of people are here _______ vacation every year. [ ]
A. in
B. at
C. on
D. with
答案:C
“BASIC”语言是一种()。
A.机器语言
B.汇编语言
C.会话语言
下列()项不属于利用矿井总风压通风。
A.用横向风墙或风障导风
B.用纵向风墙或风障导风
C.利用风筒导风
D.利用平衡巷道通风