Dear mems, thank you for your reply. The OIE knows very well about my assistantship reward. But she said, the Graduate School may not consider this assistantship as the main financial source. It is so surprising! That is the reason I need to provide my presonal bank statement in order to get a new I-20 form issued by the Graduate School! The Graduate Shool first won't give me the new I-20 (I really doubt if I need a new one!) but finally they agreed to issue one without any of my personal financial support. Also, I really don't think I should have a new I-20 Form for my visa changing inside the US. The International Office said my former I-20 is for someone to travel out of the US not for changing visa application inside the US. I checked my I-20 with others' (who have changed their visa inside the US)I-20, there is no difference except the amount of assistantship! And the modification which should be made on my new I-20 is to mark "initial attendance-change of status requested" while the former one was marked by "initial attendence to this school". I am very angry at this requirment for a new I-20, because it already delayed my submitting application material three weeks! I am afraid I couldn't get the F1 visa authorization by the time I should enroll as a full time student this August. I thought the OIE is wasting my precious time.