一般中小型单体设备，可只进行( )后，即可交付生产。

A．整机检验
B．单机试车
C．联动试车
D．投料试车

We thought of selling this old furniture, but we've decided to          it. It might be valuable.      [ ]

A. hold on to                      

B. keep up with      

C. turn to                        

D. look after