The word(s) "regretful" appears 5 time(s) in 5 verse(s) in Quran in Mohsin Khan translation.

(1) And you see those in whose hearts there is a disease (of hypocrisy), they hurry to their friendship, saying: "We fear lest some misfortune of a disaster may befall us." Perhaps Allah may bring a victory or a decision according to His Will. Then they will become regretful for what they have been keeping as a secret in themselves.

(سورة المائدة, Al-Maaida, Chapter #5, Verse #52)
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(2) (Allah) said: "In a little while, they are sure to be regretful."

(سورة المؤمنون, Al-Muminoon, Chapter #23, Verse #40)
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(3) But they killed her, and then they became regretful.

(سورة الشعراء, Ash-Shu'araa, Chapter #26, Verse #157)
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(4) O you who believe! If a Fasiq (liar - evil person) comes to you with any news, verify it, lest you should harm people in ignorance, and afterwards you become regretful for what you have done.

(سورة الحجرات, Al-Hujuraat, Chapter #49, Verse #6)
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(5) Were it Our Will, We could crumble it to dry pieces, and you would be regretful (or left in wonderment) [Tafsir Ibn Kathir].

(سورة الواقعة, Al-Waaqia, Chapter #56, Verse #65)
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