The news of this discovery could not be kept secret very long.

VOA: special.2009.02.04

Hacking believes that there were many gambling theorists who invented probability theory at various times in history but never wrote it down and kept it as a secret.

哈金相信历史上有很多赌博理论家,曾多次构想了概率论,但从来没有记录下来,并且恐为人知

耶鲁公开课 - 金融市场课程节选

But the operation had to be kept secret.

VOA: special.2010.06.24

Results will be kept secret until the night of the award ceremony: January 31 at the Staples Center in Los Angeles,California.

VOA: standard.2010.01.25

"I think it's the biggest kept secret in the world because of its value. Meanwhile,secretive parts of the secret government are sitting on suppressed technology for free energy."

VOA: standard.2009.07.31

The Washington Post reported voter turnout information allegedly kept secret by the chief envoy for the United Nations in Afghanistan,Kai Eide, provides further evidence the August 20 contest was marred by fraud.

VOA: standard.2009.10.07

He kept the bad news a secret for more than three years.

VOA: special.2010.02.07

General Grant kept details of the campaign as secret as possible.

VOA: special.2009.11.26