How come some cultural groups just won't speak English?

Well, maybe it is more comfortable for them to speak in a different language. I am white and unfortunately speak only english and I know it is hard to be around others that don't at times because you never know what they are saying...I hate when they start laughing because you never know if you are at the center of it! sTill though, I just try and ignore them...it is their right after all

if you live in the USA u speak USA English , you are right i dont like it either

well, they are speaking English to people who don't share their native language. But maybe it is faster and easier for them to express themselves in their native language with people who speak that language. I don't understand what is the problem. Well, if in a group there are people who don't understand that language, then it's rude. Otherwise, I think they have the right to choose any language they want... Besides, maybe they are just international students and don't bother calling themselves Americans... I never did

So I suppose you are all those kinds of americans who will never go visit another country anyway? Why don't you just try it once, might help you understand what it is like to not have the countries language as your first language. Might even make you more tolerant, who knows. Go to France or Spain or something, and check out what language you will be speaking on campus with your american friends.

It`s because some people feel so much more at home when they are speaking their original tongue to other people. Not only embracing their cultural, but loving themselves. If I were in India, and I was with my friends I would speak English. It`s my natural tongue, some dont even realize they are doing it. You cant expect someone from mexico to come to america, looking for a better life, and the freedom of america, and speak english 100 percent of the time. Yes, embrace english, but dont expect them to forget about their roots while doing so.

Maybe cause they are more comfortable in spoken their language to each other. that make them unique and special

I think this is a very American way of looking at things. On my campus there are heaps of people speaking all kinds of languages, but it just helps to create a diverse and interesting educational setting, where there are a range of cultural backgrounds and perspectives coming together to combine into your learning environment. What could be better than that?! Also perhaps everyone just needs to learn more languages than just English... People are realising that we are in such a disadvantage not teaching more languages other than English in schools and universities.

I THINK AND NO OFFENSE TO SOME OF THE ANSWERS,BUT THEY ARE WASTING THEIR TIME TRYING TO SCHOOL YOU BECAUSE YOU'RE OBVIOUSLY PREJUDICED AND BEAR IN MIND THAT AMERICANS DON'T SPEAK ENGLISH. I SURE AS HELL KNOW THAT WORDS LIKE AINT AND NAW ARE NOT ENGLISH WORDS,TECHNICALLY. HERE'S A QUESTION TO YOUR QUESTION: WHY DON'T YOU SPEAK THEIR LANGUAGE INSTEAD AND GO HANG WITH THEM OR ARE YOU TOO DUMB TO LEARN ANOTHER LANGUAGE?

It is natural, when speaking to a group of friends who all speak a particular language, to speak to them in that language. Your main question asks why some people "just won't speak English", but from the details of the question, I gather you are asking why they speak another language *to each other*. That's a very different thing! As to why they speak their own language... There could be many reasons. Even if they speak English, they are likely more comfortable in their own language. They can probably express nuances of meaning better in their own language. The only time they *do* get to speak their language is when speaking to each other, and they don't want to forget it. Maybe they want to pass a second language on to their children--a gift that is incomparable! (Learning more than one language in childhood actually rewires the brain--making it easier to learn *everything* throughout life.) Maybe they are discussing things that English doesn't describe accurately. And possibly they want to be able to communicate without judgmental people like you understanding them.