“善战者因其势而利导也”句中“因”的意思是（）。
A、凭借
B、依靠
C、顺着
D、依据
参考答案：C
下列属于单细胞生物的是（ ）
A．蚯蚓
B．草履虫
C．蛔虫
D．南瓜
— It's reported that the new underground line has been completed.
— Yes, but it hasn't been made clear _____ it's to be opened to traffic. [ ]
A. that
B. who
C. what
D. when
