to rupnet485
If your spouse applied I-485 depending on you, you can attach your I-140 for safety.
I think you just explain your current status and reasons to apply AP in the cover letter. There is no standard format. I applied AP for myself and my spouse. My letter is like the following.
To Whom It May Concern:
I am writing to apply for INS advance parole document for myself, xxx, and my spouse, xxx, on the basis of our adjustment of status application pending. I filed my immigration petition for alien worker, form I-140, in June 2001 and it was approved in January 2002. We then applied to adjust to permanent resident status with filling the form I-485 in January 2002 and the application was received. We seek to travel abroad during this coming Christmas holidays for emergent personal reasons. We hope to return America after temporary foreign travel with the advance parole document.
Thank you very much for your kind consideration.
Sincerely yours,
xxx
Enclosed are:
1) - 7)