I don't think your situation is the same as the question asked.

柳树下 is asking about parents and kids tax return question, under the premise that both parents are American citizens or Green card holders, and their kids too.  I don't think that you are in the same situation.  You had to file the tax returns during your college years because you were not dependant on your parents' tax returns and most likely your parents are not Americans.  The reason that I don't think your parents are not US citizens is that you know Chinese well in reading and writing.  There are very few ABC's can write Chinese well enough like you.