Do you try to teach them some new words?
You think that you should give them names- and you should. You points
to yourself and say your name several times. After a few tries, when
you points to yourself, they say your name. Then you point to them,
say "you" and then a name. You name them like this: Ted,
Bob, Betty, and Beverly. After a while they start saying tyheir names
and pointing eachother. Ted turns to you, and, to your amzement,
thanks you- in their language.