回收率是反渗透系统设计和运行的重要参数，回收率增加，反渗透的浓水含盐量（）。
A.增加
B.减少
C.不变化
D.不稳定
参考答案：A
The police were looking into the accident, hoping to find out _______ that had caused it.[ ]
A. what it was
B. what was it
C. how it was
D. how was it
龟甲、鳖甲共同具有的功效是（）
A.养血补心
B.软坚散结
C.益肾健骨
D.滋阴潜阳
E.清肺化痰
