The word(s) "sudden" appears 15 time(s) in 15 verse(s) in Quran in Mohsin Khan translation.

(1) They indeed are losers who denied their Meeting with Allah, until all of a sudden, the Hour (signs of death) is on them, and they say: "Alas for us that we gave no thought to it," while they will bear their burdens on their backs; and evil indeed are the burdens that they will bear!

(2) So, when they forgot (the warning) with which they had been reminded, We opened for them the gates of every (pleasant) thing, until in the midst of their enjoyment in that which they were given, all of a sudden, We took them (in punishment), and lo! They were plunged into destruction with deep regrets and sorrows.

(3) Say: "Tell me, if the punishment of Allah comes to you suddenly (during the night), or openly (during the day), will any be destroyed except the Zalimun (polytheists and wrong-doing people)?"

(4) And a great number of towns (their population) We destroyed (for their crimes). Our torment came upon them (suddenly) by night or while they were taking their midday nap.

(5) Then We changed the evil for the good, until they increased in number and in wealth, and said: "Our fathers were touched with evil (loss of health and calamities) and with good (prosperity)." So We seized them all of a sudden while they were unaware.

(6) They ask you about the Hour (Day of Resurrection): "When will be its appointed time?" Say: "The knowledge thereof is with my Lord (Alone). None can reveal its time but He. Heavy is its burden through the heavens and the earth. It shall not come upon you except all of a sudden." They ask you as if you have a good knowledge of it. Say: "The knowledge thereof is with Allah (Alone), but most of mankind know not."

(7) Do they then feel secure from the coming against them of the covering veil of the Torment of Allah, or of the coming against them of the (Final) Hour, all of a sudden while they perceive not?

(8) Nay, it (the Fire or the Day of Resurrection) will come upon them all of a sudden and will perplex them, and they will have no power to avert it nor will they get respite.

(9) And those who disbelieved will not cease to be in doubt about it (this Qur'an) until the Hour comes suddenly upon them, or there comes to them the torment of the Day after which there will be no night (i.e. the Day of Resurrection).

(10) It shall come to them of a sudden, while they perceive it not.