The word(s) "certainly" appears 476 time(s) in 417 verse(s) in Quran in Muhammad Habib Shakir translation.

(21) Then after sorrow He sent down security upon you, a calm coming upon a party of you, and (there was) another party whom their own souls had rendered anxious; they entertained about Allah thoughts of ignorance quite unjustly, saying: We have no hand in the affair. Say: Surely the affair is wholly (in the hands) of Allah. They conceal within their souls what they would not reveal to you. They say: Had we any hand in the affair, we would not have been slain here. Say: Had you remained in your houses, those for whom slaughter was ordained would certainly have gone forth to the places where they would be slain, and that Allah might test what was in your breasts and that He might purge what was in your hearts; and Allah knows what is in the breasts.

(22) (As for) those of you who turned back on the day when the two armies met, only the Shaitan sought to cause them to make a slip on account of some deeds they had done, and certainly Allah has pardoned them; surely Allah is Forgiving, Forbearing.

(23) And if you are slain in the way of Allah or you die, certainly forgiveness from Allah and mercy is better than what they amass.

(24) And if indeed you die or you are slain, certainly to Allah shall you be gathered together.

(25) Thus it is due to mercy from Allah that you deal with them gently, and had you been rough, hard hearted, they would certainly have dispersed from around you; pardon them therefore and ask pardon for them, and take counsel with them in the affair; so when you have decided, then place your trust in Allah; surely Allah loves those who trust.

(26) certainly Allah conferred a benefit upon the believers when He raised among them an Apostle from among themselves, reciting to them His communications and purifying them, and teaching them the Book and the wisdom, although before that they were surely in manifest error.

(27) What! when a misfortune befell you, and you had certainly afflicted (the unbelievers) with twice as much, you began to say: Whence is this? Say: It is from yourselves; surely Allah has power over all things.

(28) And that He might know the hypocrites; and it was said to them: Come, fight in Allah's way, or defend yourselves. They said: If we knew fighting, we would certainly have followed you. They were on that day much nearer to unbelief than to belief. They say with their mouths what is not in their hearts, and Allah best knows what they conceal.

(29) Allah has certainly heard the saying of those who said: Surely Allah is poor and we are rich. I will record what they say, and their killing the prophets unjustly, and I will say: Taste the chastisement of burning.

(30) You shall certainly be tried respecting your wealth and your souls, and you shall certainly hear from those who have been given the Book before you and from those who are polytheists much annoying talk; and if you are patient and guard (against evil), surely this is one of the affairs (which should be) determined upon.