My interview is scheduled about 2 months from today, I'm becoming more and more neverse for the N-400 interview. Though I studied very hard and with the help from my husband, I could only get my TOEFL score a little above 550 in the third try. I am not very comforable to talk with the immigration officer one to one in a closed room. If I'm neverse, it would be hard for me to understand the officer's questions. Does anybody here know some reference books to help me pass the English test? Thanks.