The word(s) "whether" appears 42 time(s) in 39 verse(s) in Quran in Mohsin Khan translation.

(21) But if they (disbelievers, idolaters, Jews, Christians, polytheists) turn away (from Islamic Monotheism) say (to them O Muhammad صلى الله عليه وسلم): "I give you a notice (of war as) to be known to us all alike. And I know not whether that which you are promised (i.e. the torment or the Day of Resurrection) is near or far. "

(22) Whoever thinks that Allah will not help him (Muhammad صلى الله عليه وسلم) in this world and in the Hereafter, let him stretch out a rope to the ceiling and let him strangle himself. Then let him see whether his plan will remove that whereat he rages!

(23) And those who give that (their charity) which they give (and also do other good deeds) with their hearts full of fear (whether their alms and charities have been accepted or not), because they are sure to return to their Lord (for reckoning).

(24) There is no restriction on the blind, nor any restriction on the lame, nor any restriction on the sick, nor on yourselves, if you eat from your houses, or the houses of your fathers, or the houses of your mothers, or the houses of your brothers, or the houses of your sisters, or the houses of your father's brothers, or the houses of your father's sisters, or the houses of your mother's brothers, or the houses of your mother's sisters, or (from that) whereof you hold keys, or (from the house) of a friend. No sin on you whether you eat together or apart. But when you enter the houses, greet one another with a greeting from Allah (i.e. say: السلام عليكم) As-Salamu 'Alaikum - peace be on you) blessed and good. Thus Allah makes clear the Ayat (these Verses or your religious symbols and signs) to you that you may understand.

(25) They said: "It is the same to us whether you preach or be not of those who preach.

(26) [Sulaiman (Solomon)] said: "We shall see whether you speak the truth or you are (one) of the liars.

(27) One with whom was knowledge of the Scripture said: "I will bring it to you within the twinkling of an eye!" Then when he [Sulaiman (Solomon)] saw it placed before him, he said: "This is by the Grace of my Lord - to test me whether I am grateful or ungrateful! And whoever is grateful, truly, his gratitude is for (the good of) his ownself; and whoever is ungrateful, (he is ungrateful only for the loss of his ownself). Certainly my Lord is Rich (Free of all needs), Bountiful."

(28) He said: "Disguise her throne for her that we may see whether she will be guided (to recognise her throne), or she will be one of those not guided."

(29) whether you reveal anything or conceal it, verily, Allah is Ever All-Knower of everything.

(30) It is the same to them whether you warn them or you warn them not, they will not believe.