The word(s) "certainly" appears 150 time(s) in 144 verse(s) in Quran in Mohsin Khan translation.

(111) certainly, to Allah belongs all that is in the heavens and the earth. Surely, He knows your condition and (He knows) the Day when they will be brought back to Him, then He will inform them of what they did. And Allah is All-Knower of everything.

(112) [Fir'aun (Pharaoh)] said: "If you choose an ilah (god) other than me, I will certainly put you among the prisoners."

(113) So they threw their ropes and their sticks, and said: "By the might of Fir'aun (Pharaoh), it is we who will certainly win!"

(114) One with whom was knowledge of the Scripture said: "I will bring it to you within the twinkling of an eye!" Then when he [Sulaiman (Solomon)] saw it placed before him, he said: "This is by the Grace of my Lord - to test me whether I am grateful or ungrateful! And whoever is grateful, truly, his gratitude is for (the good of) his ownself; and whoever is ungrateful, (he is ungrateful only for the loss of his ownself). certainly my Lord is Rich (Free of all needs), Bountiful."

(115) 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).

(116) 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!

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

(118) 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.

(119) 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.

(120) And those who disbelieve say: "We believe not in this Qur'an nor in that which was before it." But if you could see when the Zalimun (polytheists and wrong-doers) will be made to stand before their Lord, how they will cast the (blaming) word one to another! Those who were deemed weak will say to those who were arrogant: "Had it not been for you, we should certainly have been believers!"