>What's wrong with learning proper English and proper Spanish? That's what _I_ learned. I know the difference between proper English and slang, and same in Spanish. I would not dare use certain expressions in English when in a business setting. Same in Spanish. These people do not know the difference.

We have a few places back home where there are whole villages of minority population. They mostly learn Serbian from each other, not that much from TV or radio, and they never learn it right. One such village, close to Romanian border, although not predominantly Romanian by composition anymore, practically has its own language. Their accent is off the scale, and they have some special words that nobody else uses. Few people I met who were able to imitate their speech were guaranteed to score points for being funny.

A friend of mine learned Hungarian while being raised by his Hungarian grandmother in one of those places. And guess what - when we were later in Hungary, he flatly refused to speak the language, being aware that his way of speaking it would betray him right away - what Hungarian they speak in that place is also a heavy dialect. For a while I had to translate for him, and I have just learned some of the language. He said it was easier for me, not having any bad habits to break.