polish up
1．become bright and clean with polishing擦亮
He polished up the silverware till it shone．他把银器擦得铮亮。
2．improve改善；润色
I'll have to polish up my French before the holidays．度假前我得温习一下法语。
I think this article needs polishing up before we print it．我认为这篇文章还需润色一下才能复印。