The story is so ________that all of us are_______in it.

A．interested; interesting

B．interesting; interested

C．interested; interested

D．interesting; interesting

调速阀是组合阀，其组成是（）。

A.可调节流阀与单向阀串联

B.定差减压阀与可调节流阀并联

C.定差减压阀与可调节流阀串联

D.可调节流阀与单向阀并联