It's been estimated that wood is running out more quickly than oil and gas.

VOA: special.2010.02.01

He points out that it's estimated that for every $3 you send to UNICEF, you can save a life.

他指出,据估计,你给联合国儿童基金会每寄去3美元,就能救助一个人的性命

耶鲁公开课 - 金融市场课程节选

"It's estimated that the average commuter in our region, congestion costs that person in excess of $1000 per year in lost time."

VOA: standard.2010.07.26