受侵蚀介质作用的混凝土优先选用的水泥是（）。
A．矿渣水泥
B．硅酸盐水泥
C．火山灰水泥
D．粉煤灰水泥
E．复合水泥
参考答案：A, C, D, E
Can you make sure ______ the gold ring?
A．where Alice had put
B．where did Alice put
C．where Alice has put
D．where has Alice put
不开口于中鼻道的鼻窦是
A．额窦B．前组筛窦C．蝶窦D．上颌窦E．以上都是
