知足常乐英语怎么翻译？

A contented mind is perpetual feast. 知足常乐。 Happiness lies in contentment. 知足常乐。Happiness consists in contentment. 知足常乐。content英 ['kɒntent] 美 [ˈkɑ:ntent] n.内容;满足;（书等的）目录;容量adj.满足的，满意的;愿意的;心甘情愿的vt.使满足，使满意contentment英 [kənˈtentmənt] 美 [kənˈtɛntmənt] n.满足，满意，知足，心满意足perpetual 英[pəˈpetʃuəl] 美[pərˈpetʃuəl] adj. 永久的; 不断的; 无期限的; 四季开花的; [例句]I thought her perpetual complaints were going to prove too much for me.我想我再也受不了她无休无止的抱怨了。 lies in 在于consists in 在于Happiness consists in serving the people. 幸福在于为人民服务。