Involvement in sports, in particular, rose almost 50% from 1981 to 1997: boys now spend an average of four hours a week playing sports; girls log half that time.

特别体育运动参与率从1981年到1997年上升了近50%：男孩们现在平均每周花四个小时做运动；而女生则只花一半的时间。

youdao

That's based on all of four hours playing with it.

当然这些仅仅我只是玩了四个钟头后的感想和体验。

youdao

Four hours of sleep in the twenty-four had meant being robbed of four hours of life.

他在二十四小时里只睡四小时还嫌四小时生活时间被剥夺。

youdao

This took an average of four hours to do.

VOA: special.2010.07.14

And for the space of four hours every night, I feel no boredom.

每晚四小时的学习，我一点也不觉得无聊。

耶鲁公开课 - 政治哲学导论课程节选

A food frequency--by the way, you also have the issue of whether the particular twenty-four hours that a person is interviewed is representative of their diet overall, because you can imagine how much your food intake varies from day to day.

食物摄取频率,顺便说下,还有一个问题,就是在选取的24小时里,测试者,是不是对总体有代表性,因为你可以想象,每天事物的摄入量都是不同的

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选

The service now runs at a time of four hours, operated by East Coast.

BBC: Scotland

Americans spend an average of four hours a day watching TV, an hour of that enduring ads.

FORBES: ZAP!

Each year the course consisted of ten lectures and each lecture consisted of four hours of classroom instruction.

CNN: AllPolitics - Ethics Transcript