brush upon

1review a skillknowledgeone has learned in the past 重新学习;复习

I'll have to brush up my English before I go abroad.出国前我要温习一下英语。

He said he had to brush up on his history before the examination.他说他得在考试前复习历史。

2make clean or bright with a brush 刷净;擦亮

Your boots should be brushed up a bit.你的长统靴该搽搽亮。