---What did you do yesterday?

---My brother took two friends of _______ to play chess with us. But I don’t know

________ of them.

A．his; all

B．him; both

C．his; either

D．him; neither

（）不是进行电缆敷设用钢管的连接工作。

A．电缆管的连接，必须用丝扣和管接头连接。

B．若采用焊接时，不能直接对焊

C．擦干净钢管，做好消毒

D．连接处要套一段粗管再进行焊接，以免焊渣进入管内