What does “work off your tone” mean in this context from Modern Family? Claire: (while walking on the street with her husband, Phil, she saw a guy on the other end and immediately frowns.) Oh, don’t look. There’s that jerk, Duane. Phil: Oh, yuck. Claire: i should say sth to him, shouldn’t I? Phil: I gotta be honest. I was just **working off your tone**. Who’s Duane and why do we hate him? Is “work off” here a phrasal verb or does this work specifically in this context only? What does the part marked in stars exactly mean? Thanks in advance!