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

(21) And when ye said: O Moses! We are weary of one kind of food; so call upon thy Lord for us that He bring forth for us of that which the earth groweth - of its herbs and its cucumbers and its corn and its lentils and its onions. He said: Would ye exchange that which is higher for that which is lower? Go down to settled country, thus ye shall get that which ye demand. And humiliation and wretchedness were stamped upon them and they were visited with wrath from Allah. That was because they disbelieved in Allah's revelations and slew the prophets wrongfully. That was for their disobedience and transgression.

(22) And (remember, O Children of Israel) when We made a covenant with you and caused the mount to tower above you, (saying): Hold fast that which We have given you, and remember that which is therein, that ye may ward off (evil).

(23) And when Moses said unto his people: Lo! Allah commandeth you that ye sacrifice a cow, they said: Dost thou make game of us? He answered: Allah forbid that I should be among the foolish!

(24) And (remember) when ye slew a man and disagreed concerning it and Allah brought forth that which ye were hiding.

(25) Have ye any hope that they will be true to you when a party of them used to listen to the word of Allah, then used to change it, after they had understood it, knowingly?

(26) And when they fall in with those who believe, they say: We believe. But when they go apart one with another they say: Prate ye to them of that which Allah hath disclosed to you that they may contend with you before your Lord concerning it? Have ye then no sense?

(27) And (remember) when We made a covenant with the Children of Israel, (saying): Worship none save Allah (only), and be good to parents and to kindred and to orphans and the needy, and speak kindly to mankind; and establish worship and pay the poor-due. Then, after that, ye slid back, save a few of you, being averse.

(28) And when We made with you a covenant (saying): Shed not the blood of your people nor turn (a party of) your people out of your dwellings. Then ye ratified (Our covenant) and ye were witnesses (thereto).

(29) And verily We gave unto Moses the Scripture and We caused a train of messengers to follow after him, and We gave unto Jesus, son of Mary, clear proofs (of Allah's sovereignty), and We supported him with the Holy spirit. Is it ever so, that, when there cometh unto you a messenger (from Allah) with that which ye yourselves desire not, ye grow arrogant, and some ye disbelieve and some ye slay?

(30) And when there cometh unto them a scripture from Allah, confirming that in their possession - though before that they were asking for a signal triumph over those who disbelieved - and when there cometh unto them that which they know (to be the truth) they disbelieve therein. The curse of Allah is on disbelievers.