I don't believe, graded books are of no use.
What's the idea of reading a book if you can't get the plot or you can only guess what the characters are talking about?
If one isn't good at reading English books he can kill the time by reading Chinese books as well))
p.s. Jane Austen is a very famous English writer. To master a foreign language means not only to learn a couple of modern words, but also to acquire some knowledge about the history and the culture of the country.