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

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