The word(s) "hard" appears 62 time(s) in 58 verse(s) in Quran in Muhammad Habib Shakir translation.

(21) If good befalls you, it grieves them, and if hardship afflicts you, they say: Indeed we had taken care of our affair before; and they turn back and are glad.

(22) O Prophet! strive hard against the unbelievers and the hypocrites and be unyielding to them; and their abode is hell, and evil is the destination.

(23) And whenever a chapter is revealed, saying: Believe in Allah and strive hard along with His Apostle, those having ampleness of means ask permission of you and say: Leave us (behind), that we may be with those who sit.

(24) But the Apostle and those who believe with him strive hard with their property and their persons; and these it is who shall have the good things and these it is who shall be successful.

(25) The dwellers of the desert are very hard in unbelief and hypocrisy, and more disposed not to know the limits of what Allah has revealed to His Apostle; and Allah is Knowing, Wise.

(26) O you who believe! fight those of the unbelievers who are near to you and let them find in you hardness; and know that Allah is with those who guard (against evil).

(27) And recite to them the story of Nuh when he said to his people: O my people! if my stay and my reminding (you) by the communications of Allah is hard on you-- yet on Allah do I rely-- then resolve upon your affair and (gather) your associates, then let not your affair remain dubious to you, then have it executed against me and give me no respite:

(28) And Musa said: Our Lord! surely Thou hast given to Firon and his chiefs finery and riches in this world's life, to this end, our Lord, that they lead (people) astray from Thy way: Our Lord! destroy their riches and harden their hearts so that they believe not until they see the painful punishment.

(29) And when Our decree came to pass, We delivered Hud and those who believed with him with mercy from Us, and We delivered them from a hard chastisement.

(30) And when Our apostles came to Lut, he was grieved for them, and he lacked strength to protect them, and said: This is a hard day.