Last summer, I went back to my hometown,     the neighbors and the houses that I used to be familiar with were gone．

A．only finding

B．only to find

C．to find

D．found

刮削修复导轨时，其基准面应选择不可调的装配孔或（）作为基准。

A．不磨损的平面

B．导轨中心

C．任意