I m helping my mother with her green card renewal. One of the questions on the form asks about filing taxes for the last 3 years. She has only filed once because she lived outside the U.S. for more than 6 months during two of those years, and I only claimed her as a dependent in one of the 3 years. However, she has been physically present in the U.S. for at least 3 out of the last 5 years. How should I answer the tax filing question, and will this affect her renewal application?