The word(s) "certain" appears 498 time(s) in 437 verse(s) in Quran in Muhammad Habib Shakir translation.

(401) And certainly We have already destroyed the likes of you, but is there anyone who will mind?

(402) And certainly you know the first growth, why do you not then mind?

(403) If We pleased, We should have certainly made it broken down into pieces, then would you begin to lament:

(404) Most surely this is a certain truth.

(405) certainly We sent Our apostles with clear arguments, and sent down with them the Book and the balance that men may conduct themselves with equity; and We have made the iron, wherein is great violence and advantages to men, and that Allah may know who helps Him and His apostles in the secret; surely Allah is Strong, Mighty.

(406) And certainly We sent Nuh and Ibrahim and We gave to their offspring the (gift of) prophecy and the Book; so there are among them those who go aright, and most of them are transgressors.

(407) Allah has written down: I will most certainly prevail, I and My apostles; surely Allah is Strong, Mighty.

(408) He it is Who caused those who disbelieved of the followers of the Book to go forth from their homes at the first banishment you did not think that they would go forth, while they were certain that their fortresses would defend them against Allah; but Allah came to them whence they did not expect, and cast terror into their hearts; they demolished their houses with their own hands and the hands of the believers; therefore take a lesson, O you who have eyes!

(409) And had it not been that Allah had decreed for them the exile, He would certainly have punished them in this world, and in the hereafter they shall have chastisement of the fire.

(410) Have you not seen those who have become hypocrites? They say to those of their brethren who disbelieve from among the followers of the Book: If you are driven forth, we shall certainly go forth with you, and we will never obey any one concerning you, and if you are fought against, we will certainly help you, and Allah bears witness that they are most surely liars.