I married my husband who is illegal in 2010. I have no idea what this ITIN is or what a W-7 form is. He has no passport only a birth certificate and ID from his country. Can I file as married filing single? I need to be able to claim my student loan interest and I think I can only do that as filing jointly but he really shouldn't exist in the states. We have an immigration lawyer and are in the process of getting him a visa... please help!