警察执勤时必须佩戴警徽。

Police officers must wear their ___badges when on duty.

学生们戴着印有环保标志的徽章参加游行。

The students wore ___badges with environmental symbols during the march.

我解锁了新的成就徽章，因为连续登录了30天。

I earned new ___badges for logging in 30 days in a row.