The word(s) "dutiful" appears 16 time(s) in 16 verse(s) in Quran in Mohsin Khan translation.

(11) (And remain always) turning in repentance to Him (only), and be afraid and dutiful to Him; and perform As-Salat (Iqamat-as-Salat) and be not of Al-Mushrikun (the polytheists, idolaters, disbelievers in the Oneness of Allah).

(12) And We have enjoined on man (to be dutiful and good) to his parents. His mother bore him in weakness and hardship upon weakness and hardship, and his weaning is in two years - give thanks to Me and to your parents. Unto Me is the final destination.

(13) Lest a person should say: "Alas, my grief that I was undutiful to Allah (i.e. I have not done what Allah has ordered me to do), and I was indeed among those who mocked [at the truth! i.e. La ilaha illallah (none has the right to be worshipped but Allah), the Qur'an, and Muhammad صلى الله عليه وسلم and at the faithful believers]

(14) And We have enjoined on man to be dutiful and kind to his parents. His mother bears him with hardship. And she brings him forth with hardship, and the bearing of him, and the weaning of him is thirty months, till when he attains full strength and reaches forty years, he says: "My Lord! Grant me the power and ability that I may be grateful for Your Favour which You have bestowed upon me and upon my parents, and that I may do righteous good deeds, such as please You, and make my offspring good. Truly, I have turned to You in repentance, and truly, I am one of the Muslims (submitting to Your Will)."

(15) "That you should worship Allah (Alone), fear (be dutiful to) Him, and obey me,

(16) And they will not receive admonition unless Allah wills; He (Allah) is the One, deserving that mankind should be afraid of, and should be dutiful to Him, and should not take any Ilah (god) along with Him, and He is the One Who forgives (sins).