I've been studying english in one way or another for about 16 years now. Truth is I learnt most of it not by studying, but by reading, playing vidya, listening to music, that sort of thing.
When I was very little I traveled to Brazil and stayed there for a bit over a year. According to my parents I was almost at good at portuguese as I was at spanish, but nowadays I barely speak it. I can still understand it pretty well, but I think that's mostly because of how close the two languages are
And currently I'm self-teaching myself Latin, though my only experience up until now is 6 units of LLPSI