"Insurgencies last a long time." "But,as you look at how long it took to turn Iraq around, it was about 18 months.

VOA: standard.2010.07.22

But notice how long it took us to get there, how many centuries it took.

但是要注意到这要多长时间，它花了多少个世纪。

耶鲁公开课 - 新约课程节选

That's how long it took for an international team of scientists to excavate and analyze the fossilized skeleton of a 4.4 million year old human ancestor, Ardipithecus ramidus, which was discovered in Ethiopia.

VOA: standard.2009.12.24