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

(31) And when it is said unto them: Believe in that which Allah hath revealed, they say: We believe in that which was revealed unto us. And they disbelieve in that which cometh after it, though it is the truth confirming that which they possess. Say (unto them, O Muhammad): Why then slew ye the prophets of Allah aforetime, if ye are (indeed) believers?

(32) And when We made with you a covenant and caused the Mount to tower above you, (saying): Hold fast by that which We have given you, and hear (Our Word), they said: We hear and we rebel. And (worship of) the calf was made to sink into their hearts because of their rejection (of the covenant). Say (unto them): Evil is that which your belief enjoineth on you, if ye are believers.

(33) Is it ever so that when they make a covenant a party of them set it aside? The truth is, most of them believe not.

(34) And when there cometh unto them a messenger from Allah, confirming that which they possess, a party of those who have received the Scripture fling the Scripture of Allah behind their backs as if they knew not,

(35) The Originator of the heavens and the earth! when He decreeth a thing, He saith unto it only: Be! and it is.

(36) And guard (yourselves) against a day when no soul will in aught avail another, nor will compensation be accepted from it, nor will intercession be of use to it; nor will they be helped.

(37) And (remember) when his Lord tried Abraham with (His) commands, and he fulfilled them, He said: Lo! I have appointed thee a leader for mankind. (Abraham) said: And of my offspring (will there be leaders)? He said: My covenant includeth not wrong-doers.

(38) And when We made the House (at Makka) a resort for mankind and sanctuary, (saying): Take as your place of worship the place where Abraham stood (to pray). And We imposed a duty upon Abraham and Ishmael, (saying): Purify My house for those who go around and those who meditate therein and those who bow down and prostrate themselves (in worship).

(39) And when Abraham prayed: My Lord! Make this a region of security and bestow upon its people fruits, such of them as believe in Allah and the Last Day, He answered: As for him who disbelieveth, I shall leave him in contentment for a while, then I shall compel him to the doom of Fire - a hapless journey's end!

(40) And when Abraham and Ishmael were raising the foundations of the House, (Abraham prayed): Our Lord! Accept from us (this duty). Lo! Thou, only Thou, art the Hearer, the Knower.