口語每日一學(xué)：Sharpen up

It means to think carefully, use your intelligence
     eg: If I make a mistake, I don't want him telling me to sharpen up.
     Note:
     Sharpen up的意思是認(rèn)真思考，用用大腦
     例：如果我犯了錯(cuò)誤，我希望他別跟我說用用大腦。