下列哪些信号机以无显示为定位。()
A.复示信号机
B.遮断信号机
C.驼峰辅助信号机
D.预告信号机
参考答案:A, B
根据上下文和首字母提示,将短文填写完整。
Su Hai and Su Yang are twin s . Su Hai is as o as SuYang.
They are in the s class and they l the same. They are good at r and j . Su Hai runs f ,
but Su Yang jumps h . Su Yang is b at the long jump t Su Hai. They want to v Beijing in
2008.
我国营养学家建议我国成人日摄盐量应控制在不超过多少克为宜。()
A.2克
B.6克
C.12克
D.16克