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

(671) And remember (Hud) the brother of 'Ad, when he warned his people in Al-Ahqaf (the curved sand-hills in the southern part of Arabian Peninsula). And surely, there have passed away warners before him and after him (saying): "Worship none but Allah; truly, I fear for you the torment of a mighty Day (i.e. the Day of Resurrection)."

(672) Then, when they saw it as a dense cloud coming towards their valleys, they said: "This is a cloud bringing us rain!" Nay, but it is that (torment) which you were asking to be hastened - a wind wherein is a painful torment!

(673) Then why did those whom they had taken for alihah (gods) besides Allah, as a way of approach (to Allah) not help them? Nay, but they vanished completely from them (when there came the torment). And that was their lie, and their inventions which they had been inventing (before their destruction).

(674) And (remember) when We sent towards you (Muhammad صلى الله عليه وسلم) a group (three to ten persons) of the jinn, (quietly) listening to the Qur'an. when they stood in the presence thereof, they said: "Listen in silence!" And when it was finished, they returned to their people, as warners.

(675) And on the Day when those who disbelieve will be exposed to the Fire (it will be said to them): "Is this not the truth?" They will say: "Yes, By our Lord!" He will say: "Then taste the torment, because you used to disbelieve!"

(676) Therefore be patient (O Muhammad صلى الله عليه وسلم) as did the Messengers of strong will and be in no haste about them (disbelievers). On the Day when they will see that (torment) with which they are promised (i.e. threatened, it will be) as if they had not stayed more than an hour in a single day. (O mankind! this Qur'an is sufficient as) a clear Message (or proclamation to save yourself from destruction). But shall any be destroyed except the people who are Al-Fasiqun (the rebellious against Allah's Command, the disobedient to Allah)?

(677) So, when you meet (in fight - Jihad in Allah's Cause) those who disbelieve, smite (their) necks till when you have killed and wounded many of them, then bind a bond firmly (on them, i.e. take them as captives). Thereafter (is the time) either for generosity (i.e. free them without ransom), or ransom (according to what benefits Islam), until the war lays down its burden. Thus [you are ordered by Allah to continue in carrying out Jihad against the disbelievers till they embrace Islam and are saved from the punishment in the Hell-fire or at least come under your protection], but if it had been Allah's Will, He Himself could certainly have punished them (without you). But (He lets you fight) in order to test some of you with others. But those who are killed in the Way of Allah, He will never let their deeds be lost.

(678) And among them are some who listen to you (O Muhammad صلى الله عليه وسلم) till when they go out from you, they say to those who have received knowledge: "What has he said just now? Such are men whose hearts Allah has sealed, and they follow their lusts (evil desires).

(679) Do they then await (anything) other than the Hour, that it should come upon them suddenly? But some of its portents (indications and signs) have already come; and when it (actually) is on them, how can they benefit then by their reminder?

(680) Those who believe say: "Why is not a Surah (chapter of the Qur'an) sent down (for us)? But when a decisive Surah (explaining and ordering things) is sent down, and fighting (Jihad - holy fighting in Allah's cause) is mentioned (i.e. ordained) therein, you will see those in whose hearts is a disease (of hypocrisy) looking at you with a look of one fainting to death. But it was better for them (hypocrites, to listen to Allah and to obey Him).