Hi Behnam,
Just learn English in a funnier way. If you are studying it with "conventional" methods, switch to funnier ones. For example, watch a TV series or a movie, listen to podcasts, find a language partner or read an enjoyable novel.
These are different ways for learning languages, but they are really dynamic and active.
You can have incredible improvements if you give this way of learning a try.
In just a couple of months you will start to see some remarkable results.
Hopefully, you will find my advice useful.
Edoardo