初次投入运行的系统和大修以后的系统，在运行（）时间内，很容易发生污物堵塞的现象。
A.3-5天
B.1-2周
C.1-2月
D.10-12天
参考答案：B
简述正常菌群中的细菌变为条件致病菌的条件.
—Has the new act been passed?
—Certainly. There's only a smattering of people who ________ it.[ ]
A. agreed
B. opposed
C. approved
D. supported
