How do I know how well I know JavaScript?

Question

JavaScript

I have the basic concepts of JS in my luggage, the closure function does not baffle me, but do I know it well enough, can someone advise real practical work or outlines, there is a test on learn javascript, but it seemed educational ..

Answer 1

Go to an interview.

Answer 2

I join the "go to the interview", at the same time you will find out your value in the labor market