Thank you for your kind words！ It's been a long time ， and during the last year，i managed to get good grade in my toefl test(107) and gre(332).. Several days ago i received the admission of northwestern university!! I'm so sorry that I've seen your reply but i didn't leave a message. It is your kind words that made me see the silver lining out of the dark clouds when i was down to fxxx. Anyway，thank you very much！