One of his early hits in Jamaica, "Serious Times", had a political message.

VOA: special.2010.08.11

When he laughed, was witty, in a merry humor, one could scarce sees his eyes, and by and by, when he was serious and positive, he opened his eyes round.

当他笑时，他是睿智的，带有令人愉快的幽默，都看不见他的眼睛了，不一会儿，他变得严肃和积极了，便圆睁着眼睛。

耶鲁公开课 - 政治哲学导论课程节选

"One should work on this and stop sleeping." Russia has also suffered a serious brain drain since 1991, the report says.

VOA: standard.2010.02.03

Clark sees traffic congestion as one of the most serious problems of our time - for a variety of reasons.

VOA: standard.2010.07.26

(Test) While the United Nations has backed away from its hope of having a legally-binding treaty come out of Copenhagen, it still believes a serious agreement can be reached that will lead the way to a legally-binding one next year.

VOA: standard.2009.12.09