Otherwise,he says, there is no way to prevent them from doing this again to his children or his grandchildren.

VOA: standard.2009.09.07

Maybe there are a number of structural problems that prevent them from doing that ... and they think, maybe, that-- I think Norway may be moving that way, so we'll see in the future.

也许在结构上存在不少问题,导致他们无法做到那一点,而且他们觉得，也许-,我认为挪威会向那个方向努力的，让我们拭目以待吧。

耶鲁公开课 - 金融市场课程节选

And we remain committed to doing all we can to try to prevent Iran from becoming a nuclear weapons power.

VOA: standard.2009.06.29

He says President Obama has to prevent Israel from doing this kind of thing, and not to protect or cover up for Israel.

VOA: standard.2010.06.22

Analyst Ali Nourizadeh, of the London-based Center for Arab and Iranian Studies, says the Iranian government is doing its best to prevent students from protesting, but he thinks student determination to go ahead with Monday's rallies is stronger: "The regime has already started four,five weeks ago arresting students.

VOA: standard.2009.12.07