I am one of those people who can't speak more than one language. But I have an uncanny ear for accents. And my brain tends to think in languages. That doesn't really make sense, does it? Let me give you an example. When I was in high school, I studied French. I started in eighth grade and went until I graduated. There were days that we got so into it, that afterwards, I'd walk around for a while, thinking in French. I couldn't speak it, but I'd think in it. Very strange. I've also had episodes when I'd be hanging out with someone with some sort of accent, and I'd find myself speaking in their accent. It happens a lot when I'm out in West Texas or hanging out with my family from there. It also happens when I watch a lot of a certain kind of TV, like Doctor Who or Sherlock. After a while, I find myself thinking and speaking with a British accent. Sometimes it's terribly fun, and sometimes it's terribly annoying, and sometimes it's TERRIBLY embarrassing. I've been called out more than once for having an accent that's not technically mine. It's rather embarrassing and makes for lots of fun being made on my behalf.
I've always wanted to learn a language though, and I know bits and pieces of several languages. French, Spanish, a little Italian and a bit of others. My brain allows me to pick up bits and pieces, which is great for learning things like songs and stuff like that, but absolute crap for actually learning the languages. Maybe someday I'll be able to learn a real language and speak it fluently. Maybe if I find a man who speaks it :-)