- a mi suegro nunca lo he tratado de usted
- I've never called my father-in-law 'usted'
- se tratan de usted/tú
- they address each other as 'usted'/'tú'
- no me digas de usted
- there's no need to call me 'usted'
- tratar de tú/usted
- to address sb in an informal/formal manner using tú/usted
- tratar de tú/usted
- to address sb informally/formally using tú/usted