Language major?

I’m super interested in languages, currently romance, and I can’t think of a good way to display this passion to an admission committee (Dartmouth??). I speak french at home with my dad, so as a junior I jumped into 4 (will take ap next year). I also take Spanish at school. I was the only student to get an A+ in Spanish 3, and I actually ended up finding a way to skip 4 and go directly into AP junior year. (I currently have an A+). I started learning Portuguese on my own but I can’t seem to find a way to make my passion seem more legitimate. I would also be interested in learning Romanian since my dad is from there.

Anyway, I would definitely be interested in Romance languages as a second major, possibly with international relations? However I’m a more math science person, and international relations seems very history based…