镜板研磨工作结束后，最后应用无水酒精擦拭干净，镜面涂以透平油或洁净猪油，并覆以洁净的白纸，然后盖上毛毡进行防护
参考答案：对
I can’t remember ______ I met the man.
A．where was it
B．it was where
C．where it was that
D．where was it that
