If I was given a penny for all the times I heard that "English is easy", I would probably be rich by now.
It seems a lot of people think that English is easy. But what is "easy"? Isn't it just a mere point-of-view? What is easy for me may not be as easy for someone else. And this alone is enough to tear down the assumption that English is easy. But I can go further, and I will.
On my side, I have nothing less than one of Bernard Shaw's masterpieces: The Pygmalion. That's what we can find in the preface to the book: