citizenship for senior

(I did search before I post, no relevent posts)

My question is regarding my mom's citizenship application.

My mom got her GC and landed in US back to 2010.10, 
In between then and now, she went back to China on AP for a few days less than 2 years.

Would her 5 year residence period be reset because of those two years abroad?
Mom is 74 years old, could she take test in Chinese and interview with translator?

please share your experience if yours is similar, or give me guidance.

highly appreciate your help!