The word(s) "warning" appears 38 time(s) in 37 verse(s) in Quran in Mohsin Khan translation.

(31) And he [Lut (Lot)] indeed had warned them of Our Seizure (punishment), but they did doubt the warnings!

(32) And they indeed sought to shame his guest (by asking to commit sodomy with them). So We blinded their eyes, (saying) "Then taste you My Torment and My warnings."

(33) "Then taste you My Torment and My warnings."

(34) And indeed, warnings came to the people of Fir'aun (Pharaoh) [through Musa (Moses) and Harun (Aaron)].

(35) Or do you feel secure that He, Who is over the heaven (Allah), will not send against you a violent whirlwind? Then you shall know how (terrible) has been My warning.

(36) And We have set none but angels as guardians of the Fire. And We have fixed their number (19) only as a trial for the disbelievers, in order that the people of the Scripture (Jews and Christians) may arrive at a certainty [that this Qur'an is the truth as it agrees with their Books regarding the number (19) which is written in the Taurat (Torah) and the Injeel (Gospel)] and that the believers may increase in Faith (as this Qur'an is the truth), and that no doubt may be left for the people of the Scripture and the believers, and that those in whose hearts is a disease (of hypocrisy) and the disbelievers may say: "What Allah intends by this (curious) example ?" Thus Allah leads astray whom He wills and guides whom He wills. And none can know the hosts of your Lord but He. And this (Hell) is nothing else than a (warning) reminder to mankind.

(37) A warning to mankind -