So since I've been here, I love how French people will do something or say phrase, and think nothing of it. However, if you as a foreigner do it, you get corrected. I think this is something that would frustrate me less if I weren't 28 years old, and sometimes being corrected by people 5 to 10 years my junior. Then again, it doesn't take much to get under my skin if I'm in the wrong mood.
One of the most normal problems I run into in France is discussing time. Technically, all time in the strictest sense should be discussed on a 24 hour clock, which is what they use in France. Not a problem, in general. I learned military time when I was a kid. We had a VCR that only ran in it. Of course, in English, we'd say 4 pm as 1600 hours in that case. But no, France has to be well....French about it. So should you be discussing 6 PM in French, you write it as 18h. Now that's perfectly reasonable, but I did start to notice something.... No one says "dixhuit heures." Everyone instead says, "six heures du soir." So in reality, they're using the exact same AM/PM system as the US, but if you as a foreigner were to say "six heures du soir," expect to be corrected at least once.
There are also words that you're not supposed to use in French, especially when discussing money. Earlier I had started reading manga translated into French. I had picked up some words, among them was fric. I decided to use it when discussing something with my niece, and she was quick to correct me. The best word to use is argent. Now, that wouldn't be so bad, It's really the difference between saying money and dough in English. Here's where it gets more complicated though. Almost no one uses fric. It's a possible translation, but when people want to be casual in discussing money, the word of choice is poignon. It's about the equivalent of saying bread as far as I can tell. The hierarchy of words for money in French, as far as I can tell (from most to least preferable) is argent, liquide (which is only to be used when talking about cash), fric, and finally poignon. The correction stung slightly less, as she was in her twenties.
Just as a final reference, I was studying some books for a French exam here, and one of the first things I remember learning was that in French, you're never supposed to end a sentence with "avec." It's kind of the same sense when in English you're not supposed to end a sentence with a preposition, but it's just avec they tell you specifically to avoid in French. So a few nights later, I'm watching TV and there it is. A national television ad for what I believe was a bank, ending their sentence with avec.
So the moral of this story, or at least some sort of takeaway, is to take everything people tell you under advisement, but personally, I wouldn't trust it further than you can throw it. Although there's a French Academy of Languages, no one actually listens to a word they say unless they're writing for Le Monde. Much like English, new words are minted every day. If the language isn't changing, maybe someone from the Academy would like to explain to me the historical origins of "meuf."
I plan on having a big article this weekend about the Hunt for Red October, also known as the mad dash to Rennes every day my partner had off to find an apartment. We get the keys this Saturday, so we'll go from there.