yes. a cover letter including a list of all documents included such as checks, photos, i-485s, approved or filed I-140, three years' W-2 (1040 tax return) and job letter to show enough financial support, and other supporting documents (I-20 etc, H1-B, J-1 waiver if have) to show legal stay in US, birth certificates, marriage certificate (if needed), physical exam by USCIS designated doctors.