The word(s) "could" appears 96 time(s) in 90 verse(s) in Quran in Mohsin Khan translation.

(51) If We will, We could send down to them from the heaven a sign, to which they would bend their necks in humility.

(52) "Their account is only with my Lord, if you could (but) know.

(53) "I found a woman ruling over them: she has been given all things that could be possessed by any ruler of the earth, and she has a great throne.

(54) Say (O Muhammad صلى الله عليه وسلم): "Tell me! If Allah made the night continuous for you till the Day of Resurrection, which ilah (god) besides Allah could bring you light? Will you not then hear?"

(55) Say (O Muhammad صلى الله عليه وسلم): "Tell me! If Allah made the day continuous for you till the Day of Resurrection, which ilah (god) besides Allah could bring you night wherein you rest? Will you not then see?"

(56) So We caused the earth to swallow him and his dwelling place. Then he had no group or party to help him against Allah, nor was he one of those who could save themselves.

(57) And those who had desired (for a position like) his position the day before, began to say: "Know you not that it is Allah Who enlarges the provision or restricts it to whomsoever He pleases of His slaves. Had it not been that Allah was Gracious to us, He could have caused the earth to swallow us up (also)! Know you not that the disbelievers will never be successful.

(58) And (We destroyed also) Qarun (Korah), Fir'aun (Pharaoh), and Haman. And indeed Musa (Moses) came to them with clear Ayat (proofs, evidence, verses, lessons, signs, revelations, etc.), but they were arrogant in the land, yet they could not outstrip Us (escape Our punishment).

(59) 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."

(60) And to Solomon (We subjected) the wind, its morning (stride from sunrise till midnoon) was a month's (journey), and its afternoon (stride from the midday decline of the sun to sunset) was a month's (journey i.e. in one day he could travel two months' (journey). And We caused a fount of (molten) brass to flow for him, and there were jinn that worked in front of him, by the Leave of his Lord. And whosoever of them turned aside from Our Command, We shall cause him to taste of the torment of the blazing Fire.