Be careful what you say down here: It could get you arrested.

My daughter and I take Spanish class here in Buenos Aires. Well we can't call it spanish class because they don't really speak Spanish here in the Rio Plata region. They certainly don't speak the Tex-mex I know. Hell, they don't even speak the Spanish from Spain.

They speak Castellano.

What is the difference? A lot. It's like the old Steve Martin bit about how the French have a different word for everything! Same here but they have a different word in Castellano for everything you managed to learn in high-school spanish class, rendering all prior spanish knowledge useless.

For instance, strawberries are not fresas like in Mexico and Spain, they are frutillas here. A jacket or coat is not a chaqueta it is a campera. The list goes on and on. It is very similar to how those crazy brits have different words for things like elevator and umbrella.

But there is more. There is this whole vos sos conjugation instead of tu eres. So my most-feared part of spanish class, verb conjugations, gets all messed up down here.

Another thing that drives most Texans and Mexicans crazy is the whole "ll" sound. It gets changed to "sh" so it is not tortilla it is tortisha. It sounds worse than my New Jersey friends trying to pronounce it "tortila".

The thing that causes the most embarrassment is the large number of innocuous words that are suddenly "dirty" here. Case in point: Concha. Everybody learns that the word for sea shell is concha (see my four-year-old son's flash card above). However, here you can't say it in public because it is a very dirty word. (Think dirty slang for a female body part).

Another, word you learned in spanish 101 is the verb coger which means to take, to grab, or to catch. Everywhere else in the spanish speaking world you use it to say you want to catch a taxi or to take a bus.

Not here. In Buenos Aires, coger (pronounced co-hare) means you want to have sexual relations with the object of the sentence you use it with. You really can't say, "¡Nececito coger un Taxi!" without being hauled off to jail.

A fellow Texan and former BA expat, Brian Winter has very funny story in his book, "Long After Midnight at the Niño Bien: A Yanqui's Missteps in Argentina" about how he mistakenly approached an old lady at bus stop and asked her if he could have sexual relations with the bus.

So do yourself a favor and learn the difference between Castellano and Spanish before you come down and say something like, "Wow! Look at the size of those conchas in the window!", like I did.

What else can you not say without being arrested in Argentina these days? My favorite is "¡Estoy con el campo!"