The word(s) "certain" appears 144 time(s) in 135 verse(s) in Quran in Abdullah Yusuf Ali translation.

(71) (Pharaoh) said: "If thou dost put forward any god other than me, I will certainly put thee in prison!"

(72) So they threw their ropes and their rods, and said: "By the might of Pharaoh, it is we who will certainly win!"

(73) "I will certainly punish him with a severe penalty, or execute him, unless he bring me a clear reason (for absence)."

(74) Still less can their knowledge comprehend the Hereafter: Nay, they are in doubt and uncertainty thereanent; nay, they are blind thereunto!

(75) And it certainly is a Guide and a Mercy to those who believe.

(76) He said: "We will certainly strengthen thy arm through thy brother, and invest you both with authority, so they shall not be able to touch you: with Our Sign shall ye triumph,- you two as well as those who follow you."

(77) Moses said: "My Lord knows best who it is that comes with guidance from Him and whose end will be best in the Hereafter: certain it is that the wrong-doers will not prosper."

(78) He said: "This has been given to me because of a certain knowledge which I have." Did he not know that Allah had destroyed, before him, (whole) generations,- which were superior to him in strength and greater in the amount (of riches) they had collected? but the wicked are not called (immediately) to account for their sins.

(79) We did test those before them, and Allah will certainly know those who are true from those who are false.

(80) And Allah most certainly knows those who believe, and as certainly those who are Hypocrites.