The word(s) "certain" appears 184 time(s) in 178 verse(s) in Quran in Mohsin Khan translation.

(131) And when the Word (of torment) is fulfilled against them, We shall bring out from the earth a beast for them, to speak to them because mankind believed not with certainty in Our Ayat (Verses of the Qur'an and Prophet Muhammad صلى الله عليه وسلم).

(132) And We indeed tested those who were before them. And Allah will certainly make (it) known (the truth of) those who are true, and will certainly make (it) known (the falsehood of) those who are liars, (although Allah knows all that before putting them to test).

(133) And they ask you to hasten on the torment (for them): and had it not been for a term appointed, the torment would certainly have come to them. And surely, it will come upon them suddenly while they perceive not!

(134) O My slaves who believe! certainly, spacious is My earth. Therefore worship Me." (Alone) .

(135) So be patient (O Muhammad صلى الله عليه وسلم). Verily, the Promise of Allah is true; and let not those who have no certainty of faith, discourage you from conveying Allah's Message (which you are obliged to convey).

(136) Those who perform As-Salat (Iqamat-as-Salat) and give Zakat and they have faith in the Hereafter with certainty.

(137) And if you (O Muhammad صلى الله عليه وسلم) ask them: "Who has created the heavens and the earth," they will certainly say: "Allah." Say: "All the praises and thanks be to Allah!" But most of them know not.

(138) And if you only could see when the Mujrimun (criminals, disbelievers, polytheists, sinners) shall hang their heads before their Lord (saying): "Our Lord! We have now seen and heard, so send us back (to the world), that we will do righteous good deeds. Verily! We now believe with certainty."

(139) And We made from among them (Children of Israel), leaders, giving guidance under Our Command, when they were patient and used to believe with certainty in Our Ayat (proofs, evidence, verses, lessons, signs, revelations, etc.).

(140) If the hypocrites, and those in whose hearts is a disease (evil desire for illegal sex), and those who spread false news among the people in Al-Madinah stop not, We shall certainly let you overpower them: then they will not be able to stay in it as your neighbours but a little while.