The word(s) "duty" appears 33 time(s) in 31 verse(s) in Quran in Abdullah Yusuf Ali translation.

(1) For Hajj are the months well known. If any one undertakes that duty therein, Let there be no obscenity, nor wickedness, nor wrangling in the Hajj. And whatever good ye do, (be sure) Allah knoweth it. And take a provision (With you) for the journey, but the best of provisions is right conduct. So fear Me, o ye that are wise.

(2) For divorced women Maintenance (should be provided) on a reasonable (scale). This is a duty on the righteous.

(3) So if they dispute with thee, say: "I have submitted My whole self to Allah and so have those who follow me." And say to the People of the Book and to those who are unlearned: "Do ye (also) submit yourselves?" If they do, they are in right guidance, but if they turn back, Thy duty is to convey the Message; and in Allah's sight are (all) His servants.

(4) In it are Signs Manifest; (for example), the Station of Abraham; whoever enters it attains security; Pilgrimage thereto is a duty men owe to Allah,- those who can afford the journey; but if any deny faith, Allah stands not in need of any of His creatures.

(5) All that they said was: "Our Lord! Forgive us our sins and anything We may have done that transgressed our duty: Establish our feet firmly, and help us against those that resist Faith."

(6) O ye who believe! Do your duty to Allah, seek the means of approach unto Him, and strive with might and main in his cause: that ye may prosper.

(7) Obey Allah, and obey the Messenger, and beware (of evil): if ye do turn back, know ye that it is Our Messenger's duty to proclaim (the message) in the clearest manner.

(8) The Messenger's duty is but to proclaim (the message). But Allah knoweth all that ye reveal and ye conceal.

(9) He is the irresistible, (watching) from above over His worshippers, and He sets guardians over you. At length, when death approaches one of you, Our angels take his soul, and they never fail in their duty.

(10) On their account no responsibility falls on the righteous, but (their duty) is to remind them, that they may (learn to) fear Allah.