He had a duty to perform and there was no way back.
Now they had the next duty to perform, which did not trouble them.
He had many duties to perform before the day was over.
I'd go back to her like a man who had a sacred duty to perform.
But now he had another duty to perform for humanity.
I have duties to perform, and people depend on me.
He had a duty to perform, a mission to complete.
He had a mission, a duty to perform, and so best get on with it.
We have a democratic duty to be here and perform our duties.
"I have a very difficult duty to perform," she began in a low voice.