perk up

1. 活跃起来; 振作起来

After a few minutes, the students perked up and began a heated discussion.

过了几分钟, 学生们活跃起来, 开始了热烈的讨论。


习惯用语perk up1.(重新)活跃起来, 振作精神2.使美观; 打扮, 装饰