With English, The Difficulty Never Ends! {titles are capitalized in English}
Using English, you* come to a point where you thought you being were capable enough, but you can't be aren't fully correct when writing or you don't have a good syntax while speaking.
Living in an English-speaking community will do the job, but when you can't (do that), the only way is to study again.
Often, people will understand you anyway, but they don't correct your mistakes, so you don't learn anymore. The risk is to fall into a tautological situation where you think you are speaking (grammatically correct) English but is you are not.
You have just find your way using a similar language, not the original one.
The first step should perhaps be grammar and syntax improvement, then pronunciation and use of idiomatic phrases.
Being similar to a natural speaker of the language, as one would say, should be the way to improve, choosing his words and his ways to of saying it.
If I listen to good speakers, I will probably build up that sort of database {one word} of "ways to say it" that will sound familiar (and correct) to English speaking people.
*Only the personal pronoun 'I', is capitalized, 'you' doesn't have to be, if it's not the first word of the sentence.
With English, the Difficulty Never Ends!
When it comes to learning English, you reach the point where you thought by now you'd be good enough, yet you still make mistakes when writing, and you still don't have good syntax while speaking.
Living in an English speaking community will help overcome this, but when that's not possible, your only option is to knuckle down to studying again.
When you reach this point, people often understand you despite your errors but, as they don't correct your mistakes, you stop learning new things. You risk falling into the trap of thinking you're speaking perfect English, when in reality you're not.
At this point, you have to find a way of shaking things up and breaking those ingrained bad habits.
Your first step should perhaps be to work on improving your grammar and syntax; then focus on your pronunciation and your use of idiomatic phrases.
Mimicking native speakers, and choosing similar words and phrases, is a good way of improving.
By listening to good speakers, it's possible to build up a sort of database of "ways to say it" that will sound familiar (and correct) to native English speakers.
