蒸锅使用前，先加进水，水量以( )为准。
A．10成满
B．8成满
C．9成满
D．6成满
参考答案：B
函数y=ln（x2-x-2）的递减区间为（ ）。
He told me that he ________ here for five minutes. [ ]
A. has come
B. had arrived
C. had been
D. came
