Agreed. If you don't bother to follow the rules you already know, how do you expect to learn more? It's not like native speakers don't have problems writing co

Agreed. If you don't bother to follow the rules you already know, how do you expect to learn more? It's not like native speakers don't have problems writing correctly. At one point, I couldn't spell the word "necessary" to save my life. One day I decided I would simply refuse to write any word I didn't know how to spell without looking it up. Now I can spell almost every word I know without looking it up. I got a D (a very bad grade) on my first college essay. On every other essay I wrote, I made absolutely certain I wasn't making the same mistakes. I got a B+ (second-best grade) or A (best grade) on every essay after that. Aside from that, I would say immersion is the best thing you can do. Immersion, not language courses, is how native speakers learn to speak like natives. Devote an hour (or more) a day to reading modern English fiction and an hour (or more) to reading modern English non-fiction. Write about what you read. Ask native speakers to review what you've written. Don't just ask them to find mistakes, ask them to rephrase anything that sounds awkward how they would say it. Fluency is imitation. What you want is to say things the way a native speaker would say them, not just to say them grammatically correctly.