Fluently? Only English. But I spent 20 years in the US military, nearly 8 of them living full-time in foreign countries. So I did my best to learn at least a little of the languages I was exposed to in my travels.
I was stationed in Japan for 3 years. I learned how to get around and order food in Japanese, plus some limited conversation. I’m actually studying to read the language now. I could read Hirigana and Katakana (the Japanese alphabets) when I lived there. But it takes their students their entire school lives to learn how to read Kanji (the complex Chinese-borrowed symbols that represent entire words), so that one will keep me busy for a while.
When I was stationed in Germany, I learned some basic German, thanks to having friendly neighbors who spoke nearly fluent English. They helped me correct and improve my German language skills. But I was only in the country for a couple years, so I didn’t get very advanced with it.
I took 4 years of French in high school. I thought I was pretty decent at it, but every time I attempted to speak the language in France, the locals immediately switched over to English to converse with me.
Random related tangent: my wife and I took a vacation to Berlin once, and my wife, like me, spent several years studying French in high school. She decided to test her German language skills with the locals, and when she spoke, they immediately switched to French for her. Turns out, she speaks German with a heavy French accent. She was able to finish her conversation in French.
I’m currently studying Norwegian. My 3x great grandfather immigrated to America from Norway, and I still have living descendants of my ancestors over there. My dad and I went to visit them once, and I would like to be able to speak their native language the next time I go back. It used to be a rule that everyone in my family line learned English and Norwegian, but my grandfather died when my dad was only 2, so my dad never learned Norwegian, and thus neither did I.
I learned some extremely limited Korean. I was assigned to South Korea twice, for a year each time, and the military wouldn’t let me live off-base amongst the locals, so I didn’t get much free time to explore the country and learn the language. But I made an effort to learn some phrases so I could be polite in public, order food, and find my way back to the military base if I got lost.
Other languages that I’ve been exposed to and picked up a handful of words/phrases, but never seriously attempted to study: Italian, Arabic, Spanish, and Hawaiian.