We are worried because we do not know how long they will stay or how we will take care of them.

VOA: standard.2009.10.27

That's not a scientific term but the same psychologists were interested in studying how quickly you can-- if at all how long does it take to figure out somebody's sexual orientation?

这不是一个科学术语,这两位心理学家也很有兴趣研究,你能多快…,如果对方真的是同性恋,就能猜出他们的性取向？

耶鲁公开课 - 心理学导论课程节选

Fahmy Howeidy, a prominent Egyptian columnist, says it is not clear how long or how inclusive the new border opening will be.

VOA: standard.2010.06.01

It's not clear how extensive and long-term the damage to Gulf seafood will be.

VOA: standard.2010.05.27

The secretary general would not say when the transition might start, how long it will take, or when it might be possible to start reducing the NATO troop commitment.

VOA: standard.2009.10.23

Dollet adds that while there are other Arabic-speaking countries that do not control the Internet as much as Egypt, it is not clear how long that relative freedom will last.

VOA: standard.2009.11.16

and coalition forces to the Afghans. Announcing an increase of 30,000 U.S. troops last week, U.S.President Barack Obama said they will begin to hand over security responsibility to Afghan forces by July of 2011, but he did not say how long the transition will take.

VOA: standard.2009.12.09