grin like a Cheshire cat
面带贼笑，展示出特别开心或者暗示有某种计谋或秘密
口语·形容神秘或得意的笑
英文释义
to have a big, wide, and often mysterious or mischievous smile on one's face
例句
He grinned like a Cheshire cat after winning the lottery.
典故来源
源自《爱丽丝梦游仙境》中的柴郡猫，其笑容神秘且持久。