18 years ago I was bottom of the class in French, and by that I mean I got the lowest score in every single test for 2 years in a row — and I mean every single test. After a few short trips to France (2 weeks at a time), a little extra tuition (once a week), and most importantly, 3 months working in a French kitchen — I was fluent by any standards.
My speech was fluid, it was natural sounding and I used the same idioms and phrasing as native speakers. My accent, though not perfect, was excellent. My vocabulary wasn’t vast, but I could very quickly rephrase my thoughts on the fly to the extent that whoever I was speaking to most likely wouldn’t notice anything at all.