不懂事：She's a kid./He's immature./He's stupid/silly/naiive……

来源: 于 2009-01-21 21:57:19 [博客] [旧帖] [给我悄悄话] 本文已被阅读：次

多愁善感：She's easy to feel sad／She's always sad.／She's always unhappy.

孝顺：He's very nice and takes very good care of his parents.

仅供参考，生活中听老美就这么简单地表达。