Tax resturn I-485 question, help mx7042007-06-20 15:30:42

Hi, I requested my past three year's tax return tran from IRS. But they only show 2004, 2005 and think my 2006's tax return form might be lost. In this case, can I use the old copy of tax return form to with I-485? (I kept the copies of my 1040 forms). Thanks for your input.

what is tax return tran? is the copy of f1040?