Well for folks who believe they've spoken a different language in a past life and seem to spill out sometime in this one, you just kinda figure out which ones are repeated compared to an action.
Sorta like this word I know, udane. I think it's a real word. However, it means wait.
Dambane means like a curse.
There are other words I know, only by saying them and relating them to what I'm trying to say in english. Others may be different, but I'm not sure.
As to talking to people in the past, I get snatches of sound. Never really any basis on it though. Such as one dream I had about a fight, as usual for me, and in it there was a guy fighting beside me. I didn't know who it was, I did know what he was, cause by the end of the fight, he looked around with triumph and said 'Now that's how us Tigers do it'.
There's always missions I remember speaking to colleagues on in past life. One I was arguing I didn't want to be bitten by baby crocs and my partner was laughing and debriefing me, and in another I was communicating on best how to resolve an attempted kidnapping/hostage situation. Nothing really stands out though, unless it stays with me to waking world.
I do agree with Zan in that I'd just try to figure out what you felt, or what you noticed around you. Oft times when there's lack of sound or garbled, that there's something more important for you to focus on. I can't think of an example off top of my head, but I know it's proved worthy for me
I do hope you figure it out though ^_^
Used to have entire topics dedicated to them on other forums and many people who remembered a white city (though not always the same city).