Q: My wife & I are separated. I have a citizenship interview. I filed after 5 years of obtaining my green card. Any advice.

A: From the facts stated by you, it is obvious your naturalization application was not filed based on your marriage to a U.S citizen. However, the basis upon which you got your Green card will come into play during the naturalization application process, and likely questions may be asked at the interview depending on the situation and facts of your case. If you have any concerns about your application or its successful outcome, do consider speaking to an immigration attorney about the details of your case. Goodluck!