The word(s) "when" appears 916 time(s) in 828 verse(s) in Quran in Mohsin Khan translation.

(141) And when I (Allah) revealed to Al-Hawariyyun (the disciples) [of 'Îsa (Jesus)] to believe in Me and My Messenger, they said: "We believe. And bear witness that we are Muslims."

(142) (Remember) when Al-Hawariyyun (the disciples) said: "O 'Îsa (Jesus), son of Maryam (Mary)! Can your Lord send down to us a table spread (with food) from heaven?" 'Îsa (Jesus) said: "Fear Allah, if you are indeed believers."

(143) And (remember) when Allah will say (on the Day of Resurrection): "O 'Îsa (Jesus), son of Maryam (Mary)! Did you say unto men: 'Worship me and my mother as two gods besides Allah?' " He will say: "Glory be to You! It was not for me to say what I had no right (to say). Had I said such a thing, You would surely have known it. You know what is in my inner-self though I do not know what is in Yours; truly, You, only You, are the All-Knower of all that is hidden (and unseen).

(144) "Never did I say to them aught except what You (Allah) did command me to say: 'Worship Allah, my Lord and your Lord.' And I was a witness over them while I dwelt amongst them, but when You took me up, You were the Watcher over them; and You are a Witness to all things. (This is a great admonition and warning to the Christians of the whole world).

(145) Indeed, they rejected the truth (the Qur'an and Muhammad صلى الله عليه وسلم) when it came to them, but there will come to them the news of that (the torment) which they used to mock at.

(146) And on the Day when We shall gather them all together, then We shall say to those who joined partners (in worship with Us): "Where are your partners (false deities) whom you used to assert (as partners in worship with Allah)?"

(147) 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."

(148) 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!"

(149) If you could but see when they will be held (brought and made to stand) in front of their Lord! He will say: "Is not this (Resurrection and the taking of the accounts) the truth?" They will say: "Yes, by our Lord!" He will then say: "So taste you the torment because you used not to believe."

(150) when Our Torment reached them, why then did they not humble themselves (believe with humility)? But their hearts became hardened, and Shaitan (Satan) made fair-seeming to them that which they used to do.