The word(s) "when" appears 1006 time(s) in 918 verse(s) in Quran in Muhammad Pickthal translation.

(161) And they denied the truth when it came unto them. But there will come unto them the tidings of that which they used to deride.

(162) Of them are some who listen unto thee, but We have placed upon their hearts veils, lest they should understand, and in their ears a deafness. If they saw every token they would not believe therein; to the point that, when they come unto thee to argue with thee, the disbelievers say: This is naught else than fables of the men of old.

(163) If thou couldst see when they are set before the Fire and say: Oh, would that we might return! Then would we not deny the revelations of our Lord but we would be of the believers!

(164) If thou couldst see when they are set before their Lord! He will say: Is not this real? They will say: Yea, verily, by our Lord! He will say: Taste now the retribution for that ye used to disbelieve.

(165) They indeed are losers who deny their meeting with Allah until, when the Hour cometh on them suddenly, they cry: Alas for us, that we neglected it! They bear upon their backs their burdens. Ah, evil is that which they bear!

(166) If only, when Our disaster came on them, they had been humble! But their hearts were hardened and the devil made all that they used to do seem fair unto them!

(167) Then, when they forgot that whereof they had been reminded, We opened unto them the gates of all things till, even as they were rejoicing in that which they were given, We seized them unawares, and lo! they were dumbfounded.

(168) And when those who believe in Our revelations come unto thee, say: Peace be unto you! Your Lord hath prescribed for Himself mercy, that whoso of you doeth evil through ignorance and repenteth afterward thereof and doeth right, (for him) lo! He is Forgiving, Merciful.

(169) He is the Omnipotent over His slaves. He sendeth guardians over you until, when death cometh unto one of you, Our messengers receive him, and they neglect not.

(170) And when thou seest those who meddle with Our revelations, withdraw from them until they meddle with another topic. And if the devil cause thee to forget, sit not, after the remembrance, with the congregation of wrong-doers.