The word(s) "but" appears 1287 time(s) in 1137 verse(s) in Quran in Mohsin Khan translation.

(231) Say (O Muhammad صلى الله عليه وسلم): "Shall I take as a Wali (Helper, Protector, Lord or God) any other than Allah, the Creator of the heavens and the earth? And it is He Who feeds but is not fed." Say: "Verily, I am commanded to be the first of those who submit themselves to Allah (as Muslims)." And be not you (O Muhammad صلى الله عليه وسلم) of the Mushrikun [polytheists, pagans, idolaters and disbelievers in the Oneness of Allah]. (Tafsir Al-Qurtubi)

(232) And if Allah touches you with harm, none can remove it but He, and if He touches you with good, then He is Able to do all things.

(233) Say (O Muhammad صلى الله عليه وسلم): "What thing is the most great in witness?" Say: "Allah (the Most Great!) is Witness between me and you; this Qur'an has been revealed to me that I may therewith warn you and whomsoever it may reach. Can you verily bear witness that besides Allah there are other alihah (gods)?" Say "I bear no (such) witness!" Say: "but in truth He (Allah) is the only one Ilah (God). And truly I am innocent of what you join in worship with Him."

(234) Those to whom We have given the Scripture (Jews and Christians) recognize him (i.e. Muhammad صلى الله عليه وسلم as a Messenger of Allah, and they also know that there is no Ilah (God) but Allah and Islam is Allah's Religion), as they recognize their own sons. Those who have lost (destroyed) themselves will not believe. (Tafsir At-Tabari).

(235) There will then be (left) no Fitnah (excuses or statements or arguments) for them but to say: "By Allah, our Lord, we were not those who joined others in worship with Allah."

(236) Look! How they lie against themselves! but the (lie) which they invented will disappear from them.

(237) And of them there are some who listen to you; but We have set veils on their hearts, so they understand it not, and deafness in their ears; and even if they see every one of the Ayat (proofs, evidence, verses, lessons, signs, revelations, etc.) they will not believe therein; to the point that when they come to you to argue with you, the disbelievers say: "These are nothing but tales of the men of old."

(238) And they prevent others from him (from following Prophet Muhammad صلى الله عليه وسلم) and they themselves keep away from him, and (by doing so) they destroy not but their ownselves, yet they perceive (it) not.

(239) If you could but see when they will be held over the (Hell) Fire! They will say: "Would that we were but sent back (to the world)! Then we would not deny the Ayat (proofs, evidence, verses, lessons, revelations, etc.) of our Lord, and we would be of the believers!"

(240) Nay, it has become manifest to them what they had been concealing before. but if they were returned (to the world), they would certainly revert to that which they were forbidden. And indeed they are liars.