The word(s) "ungrateful" appears 26 time(s) in 24 verse(s) in Quran in Abdullah Yusuf Ali translation.

(11) Said one who had knowledge of the Book: "I will bring it to thee within the twinkling of an eye!" Then when (Solomon) saw it placed firmly before him, he said: "This is by the Grace of my Lord!- to test me whether I am grateful or ungrateful! and if any is grateful, truly his gratitude is (a gain) for his own soul; but if any is ungrateful, truly my Lord is Free of all Needs, Supreme in Honour!"

(12) But verily thy Lord is full of grace to mankind: Yet most of them are ungrateful.

(13) Disdaining ungratefully Our gifts, and giving themselves up to (worldly) enjoyment! But soon will they know.

(14) And if We (but) send a Wind from which they see (their tilth) turn yellow,- behold, they become, thereafter, ungrateful (Unbelievers)!

(15) we bestowed (in the past) Wisdom on Luqman: "Show (thy) gratitude to Allah." Any who is (so) grateful does so to the profit of his own soul: but if any is ungrateful, verily Allah is free of all wants, Worthy of all praise.

(16) When a wave covers them like the canopy (of clouds), they call to Allah, offering Him sincere devotion. But when He has delivered them safely to land, there are among them those that halt between (right and wrong). But none reject Our Signs except only a perfidious ungrateful (wretch)!

(17) That was the Requital We gave them because they ungratefully rejected Faith: and never do We give (such) requital except to such as are ungrateful rejecters.

(18) Those who had been despised will say to the arrogant ones: "Nay! it was a plot (of yours) by day and by night: Behold! Ye (constantly) ordered us to be ungrateful to Allah and to attribute equals to Him!" They will declare (their) repentance when they see the Penalty: We shall put yokes on the necks of the Unbelievers: It would only be a requital for their (ill) Deeds.

(19) But those who reject (Allah) - for them will be the Fire of Hell: No term shall be determined for them, so they should die, nor shall its Penalty be lightened for them. Thus do We reward every ungrateful one!

(20) Is it not to Allah that sincere devotion is due? But those who take for protectors other than Allah (say): "We only serve them in order that they may bring us nearer to Allah." Truly Allah will judge between them in that wherein they differ. But Allah guides not such as are false and ungrateful.