太担心的话， 写个伊妹儿给他，上次我毕业的时候， 那位

教授为难我，就是不给我的论文过关，我连夜按他的意见改了一遍， 又诚恳地写了一信， 称自己是新手，会从他的课里learn a lesson ..., and I really need to pass to graduate on time .., so finally , he give me a pass, you need learn a lesson, that's very important,always ask his opinion, so
you still have chance to make up,