掩护式液压支架控制元件的基本组成部分是（）等。
A、马达
B、控制阀
C、油管
D、支柱
E、操纵阀
参考答案：B, E
French _________ English _________ having gender(性的区别) for all nouns.
A．different from; in
B．is different; from
C．differs from; in
D．differs, from
调度系统“两票”指的是什么？
