国家领导机关用于向国内外宣布重要事项，常用( )。
A．请示 B．决定 C．通告 D．公告
参考答案：D
He was told that it would be at least three more months _____ he could recover and return to work.
[ ]
A. when
B. before
C. since
D. that
刹车压力指示器指针在绿区范围内，下面哪种说法正确（）
A.储压器只向1号刹车提供压力
B.储压器可用于停留刹车
C.储压器不可用于停留刹车
