Since two thousand one she has worked with the United Nations Refugee Agency to raise public awareness about the serious problems of refugees around the world.

VOA: special.2009.05.08

And it turned out that another, not quite as deadly, but still very serious disease called syphilis was also common in this part of the world at that time.

现在已知另外一种疾病,它并不完全致命但也很严重,它叫梅毒,在那时的一些地方也很常见

耶鲁公开课 - 生物医学工程探索课程节选

Unemployment is a serious issue in many parts of the world.

在世界很多地方，失业率都是一个严重的问题。

就业很难 - SpeakingMax英语口语达人

"Definitely with something as relevant in our world as genetic research, there are serious moral and ethical concerns and responsibility that is necessary.

VOA: standard.2010.06.09

Tuesday marks the eighth day of climate talks and with world leaders arriving, analysts say it is time to make serious progress with the major issues.

VOA: standard.2009.12.17

"What we are finding is that migrant workers, particularly irregular migrant workers, very often young women, around the world are at tremendous risk of serious exploitation," .

VOA: standard.2009.08.21

Heller's surfing adventure took him to the other side of the Pacific Ocean, where he became more aware of some serious environmental issues threatening the world's oceans.

VOA: standard.2010.08.04

We cannot guess his motives. We just have to deal with the reality: that a North Korea that is proliferating weapons and missiles is a serious threat and danger to the world."

VOA: standard.2009.06.14

In the report, called "Heads in the Sand", the group says a serious decline in the supply of oil coupled with increasing demand and few new projects planned, means the world needs to move away from oil.

VOA: standard.2009.10.20

"And that's the duty of everyone who believes in justice and in deterring the gravest and most serious types of crimes that the United Nations was partially set up to prevent after the Second World War, and continues to fail to prevent."

VOA: standard.2009.09.07