The word(s) "once" appears 85 time(s) in 79 verse(s) in Quran in Muhammad Habib Shakir translation.

(31) And certainly We lodged the children of Israel in a goodly abode and We provided them with good things; but they did not disagree until the knowledge had come to them; surely your Lord will judge between them on the resurrection day concerning that in which they disagreed.

(32) Now surely they fold up their breasts that they may conceal (their enmity) from Him; now surely, when they use their garments as a covering, He knows what they conceal and what they make public; surely He knows what is in the breasts.

(33) But when he saw that their hands were not extended towards it, he deemed them strange and conceived fear of them. They said: Fear not, surely we are sent to Lut's people.

(34) And there came travellers and they sent their water-drawer and he let down his bucket. He said: O good news! this is a youth; and they concealed him as an article of merchandise, and Allah knew what they did.

(35) O my two mates of the prison! as for one of you, he shall give his lord to drink wine; and as for the other, he shall be crucified, so that the birds shall eat from his head, the matter is decreed concerning which you inquired.

(36) Alike (to Him) among you is he who conceals (his) words and he who speaks them openly, and he who hides himself by night and (who) goes forth by day.

(37) And the thunder declares His glory with His praise, and the angels too for awe of Him; and He sends the thunderbolts and smites with them whom He pleases, yet they dispute concerning Allah, and He is mighty in prowess.

(38) And Allah knows what you conceal and what you do openly.

(39) The Sabbath was ordained only for those who differed about it, and most surely your Lord will judge between them on the resurrection day concerning that about which they differed.

(40) (Some) say: (They are) three, the fourth of them being their dog; and (others) say: Five, the sixth of them being their dog, making conjectures at what is unknown; and (others yet) say: Seven, and the eighth of them is their dog. Say: My Lord best knows their number, none knows them but a few; therefore contend not in the matter of them but with an outward contention, and do not question concerning them any of them.