The word(s) "plain" appears 82 time(s) in 82 verse(s) in Quran in Muhammad Pickthal translation.

(1) And when ye said: O Moses! We will not believe in thee till we see Allah plainly; and even while ye gazed the lightning seized you.

(2) Or would ye question your messenger as Moses was questioned aforetime? He who chooseth disbelief instead of faith, verily he hath gone astray from a plain road.

(3) They question thee about strong drink and games of chance. Say: In both is great sin, and (some) utility for men; but the sin of them is greater than their usefulness. And they ask thee what they ought to spend. Say: that which is superfluous. Thus Allah maketh plain to you (His) revelations, that haply ye may reflect.

(4) Would any of you like to have a garden of palm-trees and vines, with rivers flowing underneath it, with all kinds of fruit for him therein; and old age hath stricken him and he hath feeble offspring; and a fiery whirlwind striketh it and it is (all) consumed by fire. Thus Allah maketh plain His revelations unto you, in order that ye may give thought.

(5) He it is Who hath revealed unto thee (Muhammad) the Scripture wherein are clear revelations - they are the substance of the Book - and others (which are) allegorical. But those in whose hearts is doubt pursue, forsooth, that which is allegorical seeking (to cause) dissension by seeking to explain it. None knoweth its explanation save Allah. And those who are of sound instruction say: We believe therein; the whole is from our Lord; but only men of understanding really heed.

(6) Wherein are plain memorials (of Allah's guidance); the place where Abraham stood up to pray; and whosoever entereth it is safe. And pilgrimage to the House is a duty unto Allah for mankind, for him who can find a way thither. As for him who disbelieveth, (let him know that) lo! Allah is Independent of (all) creatures.

(7) O ye who believe! Take not for intimates others than your own folk, who would spare no pains to ruin you; they love to hamper you. Hatred is revealed by (the utterance of) their mouths, but that which their breasts hide is greater. We have made plain for you the revelations if ye will understand.

(8) Allah would explain to you and guide you by the examples of those who were before you, and would turn to you in mercy. Allah is Knower, Wise.

(9) Those are they, the secrets of whose hearts Allah knoweth. So oppose them and admonish them, and address them in plain terms about their souls.

(10) The people of the Scripture ask of thee that thou shouldst cause an (actual) Book to descend upon them from heaven. They asked a greater thing of Moses aforetime, for they said: Show us Allah plainly. The storm of lightning seized them for their wickedness. Then (even) after that) they chose the calf (for worship) after clear proofs (of Allah's Sovereignty) had come unto them. And We forgave them that! And We bestowed on Moses evident authority.