The word(s) "could" appears 77 time(s) in 75 verse(s) in Quran in Muhammad Pickthal translation.

(1) The lightning almost snatcheth away their sight from them. As often as it flasheth forth for them they walk therein, and when it darkeneth against them they stand still. If Allah willed, He could destroy their hearing and their sight. Lo! Allah is able to do all things.

(2) Upon the world and the Hereafter. And they question thee concerning orphans. Say: To improve their lot is best. And if ye mingle your affairs with theirs, then (they are) your brothers. Allah knoweth him who spoileth from him who improveth. Had Allah willed He could have overburdened you. Allah is Mighty, Wise.

(3) Except those who seek refuge with a people between whom and you there is a covenant, or (those who) come unto you because their hearts forbid them to make war on you or make war on their own folk. Had Allah willed He could have given them power over you so that assuredly they would have fought you. So, if they hold aloof from you and wage not war against you and offer you peace, Allah alloweth you no way against them.

(4) Lo! as for those whom the angels take (in death) while they wrong themselves, (the angels) will ask: In what were ye engaged? They will say: We were oppressed in the land. (The angels) will say: Was not Allah's earth spacious that ye could have migrated therein? As for such, their habitation will be hell, an evil journey's end;

(5) And unto thee have We revealed the Scripture with the truth, confirming whatever Scripture was before it, and a watcher over it. So judge between them by that which Allah hath revealed, and follow not their desires away from the truth which hath come unto thee. For each We have appointed a divine law and a traced-out way. Had Allah willed He could have made you one community. But that He may try you by that which He hath given you (He hath made you as ye are). So vie one with another in good works. Unto Allah ye will all return, and He will then inform you of that wherein ye differ.

(6) Had we sent down unto thee (Muhammad) (actual) writing upon parchment, so that they could feel it with their hands, those who disbelieve would have said: This is naught else than mere magic.

(7) If thou couldst see when they are set before the Fire and say: Oh, would that we might return! Then would we not deny the revelations of our Lord but we would be of the believers!

(8) If thou couldst see when they are set before their Lord! He will say: Is not this real? They will say: Yea, verily, by our Lord! He will say: Taste now the retribution for that ye used to disbelieve.

(9) And if their aversion is grievous unto thee, then, if thou canst, seek a way down into the earth or a ladder unto the sky that thou mayst bring unto them a portent (to convince them all)! - If Allah willed, He could have brought them all together to the guidance - So be not thou among the foolish ones.

(10) Say: Have ye imagined, if Allah should take away your hearing and your sight and seal your hearts, Who is the Allah Who could restore it to you save Allah? See how We display the revelations unto them! Yet still they turn away.