I'm Greek, been living in the US for the past 4 years of my life. I had two very large spikes in my English knowledge during my life. First one was when I actu

I'm Greek, been living in the US for the past 4 years of my life. I had two very large spikes in my English knowledge during my life. First one was when I actually started taking English classes that were good. That was in my private middle/high-school. In a lot of countries public education does not care enough about English and a lot of classes are half-assed. Another option for this would be private afternoon lessons. This really helped me understand the grammar, syntax, put effort in learning new essential vocabulary. The second big spike occurred when I got into the IB program at my high school, and all classes were taught in English. Any professor interactions were also usually in English. The whole atmosphere created by this encouraged me and a lot of my friends to start talking in English to each other on a daily basis, which really helped with talking, and making the language feel way more natural. This is also when I started "thinking" in English regularly. But I feel like the most important thing was the constant consumption of English content. I read a lot of books in English, and underlined any words I didn't know, looked them up later (kind of a tangent, but for some reason I found Greek writing to be very corny, while English writing/poetry seemed way cooler in my eyes. So that helped a lot). I watched a lot of YouTube, pirated movies without subtitles, and played a lot of games that were in English. That constant exposure and willingness to learn the language was probably the biggest factor, but I'm unsure of how good my English would be today if I hadn't started serious English lessons or didn't have friends that I would speak English to.