Simlish
Simlish is the language of the Sims. It is a mixture of Ukrainian and Tagalog. It can be learned by studying the Sims' speech in certain situations. There isn't an official simlish dictionary, but a good dictionary is found here. It can be assumed that Simlish is the official language of SimNation.
~Simlish`
I don't know the language nor do I claim to. I'm just giving some advice. You can figure it out byu yourself if you pay attention enough and search for repeated words in different sims. Its amazing how much it does repeat.