B1
something that you have to do because it is part of your job, or something that you feel is the right thing to do
Dictionary examples:
As a student, my duty is to perfect the art of last-minute studying. (0.0)
It's my duty to watch funny cat videos during work breaks. (0.0)
My duty as a superhero is to save cats from trees and eat donuts. (0.0)
He only went to see her out of a sense of duty. (27.7)
I felt it was my duty to tell them the truth. (31.2)