More than 150,000 people have left their homes in Burkina Faso, many in the capital Ouagadougou, where the United Nations says the amount of rain that fell in one day last week equals one-quarter of the nation's average annual rainfall.

VOA: standard.2009.09.06

Americans spend the most time out of any other people in the world volunteering in average four hours a week, volunteering outside their job which may also have a social objective more than any other people in the world.

比其他任何人所花的时间都多,平均每周有四个小时做志愿者的工作，做与自身工作无关的善事,他们比世界上其他人更具社会目标。

哈佛公开课 - 幸福课课程节选

Americans spend the most time out of any other people in the world volunteering in average four hours a week, volunteering outside their job which may also have a social objective more than any other people in the world.

比其他任何人所花的时间都多,平均每周有四个小时做志愿者的工作，做与自身工作无关的善事,他们比世界上其他人更具社会目标。

哈佛公开课 - 幸福课课程节选