The word(s) "not" appears 1837 time(s) in 1517 verse(s) in Quran in Abdullah Yusuf Ali translation.

(1261) "And when it was said that the promise of Allah was true, and that the Hour- there was no doubt about its (coming), ye used to say, 'We know not what is the hour: we only think it is an idea, and we have no firm assurance.'"

(1262) "This, because ye used to take the Signs of Allah in jest, and the life of the world deceived you:" (From) that Day, therefore, they shall not be taken out thence, nor shall they be received into Grace.

(1263) We created not the heavens and the earth and all between them but for just ends, and for a Term Appointed: But those who reject Faith turn away from that whereof they are warned.

(1264) And who is more astray than one who invokes besides Allah, such as will not answer him to the Day of Judgment, and who (in fact) are unconscious of their call (to them)?

(1265) Say: "See ye? If (this teaching) be from Allah, and ye reject it, and a witness from among the Children of Israel testifies to its similarity (with earlier scripture), and has believed while ye are arrogant, (how unjust ye are!) truly, Allah guides not a people unjust."

(1266) The Unbelievers say of those who believe: "If (this Message) were a good thing, (such men) would not have gone to it first, before us!" And seeing that they guide not themselves thereby, they will say, "this is an (old,) falsehood!"

(1267) But (there is one) who says to his parents, "Fie on you! Do ye hold out the promise to me that I shall be raised up, even though generations have passed before me (without rising again)?" And they two seek Allah's aid, (and rebuke the son): "Woe to thee! Have faith! for the promise of Allah is true." But he says, "This is nothing but tales of the ancients!"

(1268) "Everything will it destroy by the command of its Lord!" Then by the morning they - nothing was to be seen but (the ruins of) their houses! thus do We recompense those given to sin!

(1269) And We had firmly established them in a (prosperity and) power which We have not given to you (ye Quraish!) and We had endowed them with (faculties of) hearing, seeing, heart and intellect: but of no profit to them were their (faculties of) hearing, sight, and heart and intellect, when they went on rejecting the Signs of Allah; and they were (completely) encircled by that which they used to mock at!

(1270) "If any does not hearken to the one who invites (us) to Allah, he cannot frustrate (Allah's Plan) on earth, and no protectors can he have besides Allah: such men (wander) in manifest error."