[Miss Marple]

How are you going to decide who is trustworthy?

The Defense Language Institute is expert at teaching languages in a short period. My first husband was a graduate of the Russian program, and was quite fluent in Russian by the time he graduated.

[Spruce]

My daughter is there now studying Mandarin.

[Dogbert41]

I graduated the basic russian course back in 86. It was tough, I'll tell ya, and that was before all this nice equipement and the internet. DLI in Monterey was one heck of a nice place to live though. Wish I were younger to do it all over again, only in one of the Arabic languages or Persian...

As for hiring trustworthy natives, when dealing with intel, there's only trustworthy Americans who have passed a background investgation and received proper clearances. That's just life. And what you get in return is one well trained professional soldier, airmen, marine or sailer.