灌注混凝土为避免产生离析现象，拌合物自由卸落高度不得超过（）。
A.5m
B.3m
C.2m
D.1m
参考答案：C
既用于疝气疼痛，又可用于寒性痛经的药物有（）
A.乌药
B.香附
C.小茴香
D.荔枝核
E.川楝子
I think it is a very interesting book is well worth reading, I have never read before.
A．that; the one
B．which; one
C．which; the one
D．what; one
