Obviously doing the best he can to explain the trouble in English. This is what it sounds like he's saying to me: the car starts and idles fine, when he starts to give it gas it's also okay, but when he lets off on the gas it wants to stall. When he gives it gas again it acts normal again.

If that's correct, then it would help to know what model, year and engine it is.
What happens after letting up on the pedal if you don't give it gas again, will it actually stall, or does it just give a big hesitation and catch an idle again?
Does it only happen cold?, warm?, all the time?
Was there anything unusual you noticed before this started to happen?

First thing that came to mind was cracked hoses on the IAC, or a bad IAC valve. But that might give a few indications it was going bad before getting to this point.
Also the throttle micro switch that lets the fuel system know it should be in idle mode might have a similar affect if it isn't working properly?