Scientists have believed that S.I.V.did not cause a similar immune system problem for primates.

VOA: special.2009.09.08

"Let's not forget that he has a tremendous corruption problem, not knowing who to trust within his own ranks at times."

VOA: standard.2009.12.18

But his mother's claim that he is a 16-year-old juvenile could pose a problem for prosecutors seeking the maximum sentence of life imprisonment.

VOA: standard.2009.04.22

"I think it is very important that the U.S.taxpayer not subsidize a project which will help Ahmadinejad out of his gasoline shortage problem,"

VOA: standard.2009.06.23

But there's a problem. That money may never get past the Israeli blockade.

VOA: standard.2010.06.17

"It's part of the problem of the entertainment and tourist industry that you are so dependent upon a buoyant economy, because one of the first things that people cut is their discretionary leisure spending."

VOA: standard.2010.05.04

"We have to do this because it's a problem that is today in Greece, but if we don't fix it in Greece it may have a lot of consequences on the rest of the European Union."

VOA: standard.2010.04.28

Obama's got a problem with the Democrats. He's got a different kind of problem the Republicans, and I think there is every reason to think that Obama would like for the build-down to be meaningful."

VOA: standard.2010.07.30

are very similar genetically. "And that's a real problem when you're trying to overcome new insect or disease threats or pressures, or trying to breed a plant that's more water efficient, or even finding genetic variation for water production."

VOA: standard.2010.02.01