I speak Spanish and it always surprises me how much Romanian I can understand. Now I know that Romanian and Spanish are 2 of 5 "romance languages" in the world, so it makes sense. I always expected Portuguese and Italian to make that list, but had no idea an Eastern European country did too.
I found this out about 10 years ago when I was dating a Romanian girl. While sitting in a car, she got on the phone with her sister, and started speaking Romanian, and she was trash talking me

she (and me!) had no idea I could practically understand.