NO english?? None at all? Yeesh. Have they just moved here, or have they not taught him any at all?
Well, he is going to have to learn sometime. And if you are okay with taking it on, I say go for it!!
Perhaps you can make up some sort of flashcards? With pictures of your basic communication ideas? You can use it to ask him things (ie: hold up a picture of food and say "are you hungry?") or just to try to let him know what is going on (ie: hold up a picture of a playground and say "it's time to play outside!")
On the plus side, kids that age learn amazingly quickly.
Good luck!