You say potahto and I say potayto
I have an Honors degree from Trinity College Dublin in Modern Languages & Literature. My major was French, and my minor was Italian. In French literature, I specialized in Voltaire; in Italian literature, Dante. My MA thesis was on Albert Memmi, probably best known for Portrait du colonisé (Portrait of the Colonized), which I wrote in French.
I grew up with many languages around me, and as far back as I can remember, I spoke two: English and French. I had a facility for languages, as well as a fascination, so I picked up several more by ear by the time I was in my teens. If you have a good ear, you can mimic accents, too. I went through a phase where I wanted to speak "uncommon" languages, so, yes, I even took a course on Ki-Swahili (ah, youth, the years during which you believe you can do anything and that anything is possible). I studied Russian for a year when I was 18, which was useful for reading signs and subway stops in Moscow many years later (with my fellow journalists booking me for side trips because of that). While at university, I joined an after-hours' Irish language class, both for something to do and wanting to learn how to read a language that, written, fairly defeated me with its silent letters and shifting pronunciations... Tragically, I didn't last because I got things right away but my fellow students were a little slower and I was impatient and couldn't stand the repetition.... I have had to cultivate patience since then....
You may wonder how I managed to keep all those languages straight. I have no idea. But I did, and I do -- except when I attempt to speak Spanish, I invariably lapse into Italian. When I was sent to Spain by a Toronto travel magazine to write about the Camino, it kept happening all the time, but we understood each other, so there were no problems! The one time I did NOT lapse into Italian was at a café counter where I was ordering coffee and various items of food in what I believed to be spotless Spanish. The server asked me: "Are you Italian?" I was flabbergasted. "Why?" I asked him. "Because you have an Italian accent and your gestures are Italian." When I listened to myself, I saw that he was right: I did have an Italian accent when speaking Spanish. My friend Marina straightened that out for me. She is originally from Madrid and offered me Spanish lessons in return for a painting. So now I can speak Spanish with a Castillian accent (but... I still lapse into Italian!!!!)
With my primary two languages, it's a matter of shifting my language mentally: For English, I think in English. For French, I think in French.
My maternal grandfather was a professor of philology and a journalist. I believe I get it from him!