Today I went to OIE. That guy gave me a piece of paper. He said I just need to follow the application procedure on the paper:
1. Completed Form I-539 with $140.00 fee (check or money order made payable to INS);
2. Original Form I-20 signed and dated;
3. Copy of both sides of form I-94;
4. Financial verification;
5. Copies of your spouse's valid Immigration forma: I-94,I-20 ID;
6. Copies of the pages in each individual's passport that include biographical information,   passport picture, and passport expirtation.

there is also a note:
NOTE: If you have been offered an assistantship, please include and highlight in your letter:"please grant expedite assistantsgip pending." Also, write on bottom left corner of the enelope "Expedite:Assistantship pending."

I am wondering just these 6 items is enough. Because there are some article on this forum said more material should be submitted.

BTW, which state's abbreviation is NE?

我想转身份就和在国内签证一样，f2签证也只需要护照，结婚证，i-20就够了，可没几个人只带这么点的（牛人除外),总要带些别的侧面证明，转身份的时候同理大概也是材料越充足越好吧

还需要结婚证吗？

每个区的INS所需的材料不同,我只知道我这里属于 Nebreska Linon(不知道有没有拼错),所需的材料很少,很方便,效率也不错.BOOBOO 我觉得我们可能是一样的.

对，他们让我把材料寄到NE。 linclon的地方，看来咱们是一样的。