Piano's Wonderland

Although it's hard not to mind what she said, I still need to be myself instead of getting lost.
The reason why I was very frustrated was she denied all of my efforts and said that I never did any improvements after she told me some suggestions!!!
She believes what she sees and never thinks about that we also have done many things she doesn't know. What the *****............
I did so many efforts on teaching and thought many different way teaching them English so that students can learn more.
And she said so because she thought that her son haven't improved "a lot."
I promise that he have learned well here though he is not the best.
I really don't know what to so but feel mad and frustrated.
If I lose this student because of this reason, I'll be very 不甘心!!!!!
I have done what I have to do or not to do, and do as best as I can, and she still thinks I'm don't do it and not good enough.....
Well, it's really the time to say goodbye to the kid and I'm glad to teach him, the good boy.
That's it.