How to increase the percentage of knowledge of the English language
Hello, I have the IGCSE diploma and so here I used the checkpoints and I have finished the lessons with score 56%. How can I raise it? I also bought an exam with lingots but nothing changed. Thanks on the advance
Don't worry about the fluency percentage.
It can never go to 100% because that would imply complete fluency in the language, which is a level that Duolingo simply cannot measure, because it doesn't have the breadth of vocabulary and grammar to tell.
So the maximum fluency level you can attain on Duolingo will be in the range 50-70%, depending on the course.
When you're learning, it can be fun to see the number go up slowly. (But it might also go down inexplicably by a point or two.)
But once you've attained a certain level, it's best to ignore Duo's fluency level, I think. And judging by your words, you may be too skilled to obtain much benefit from Duolingo.
You can try repeating some sentences here or focus on particular points of grammar that give you difficulty, but it may be better to start using other resources such as live conversation via Skype, English videos, reading books, etc.