The word(s) "lesson" appears 168 time(s) in 166 verse(s) in Quran in Mohsin Khan translation.

(61) If you ask them (about this), they declare: "We were only talking idly and joking." Say: "Was it at Allah (عز وجل), and His Ayat (proofs, evidence, verses, lessons, signs, revelations) and His Messenger (صلى الله عليه وسلم) that you were mocking?"

(62) See they not that they are put in trial once or twice every year (with different kinds of calamities, disease, famine)? Yet, they turn not in repentance, nor do they learn a lesson (from it).

(63) It is He Who made the sun a shining thing and the moon as a light and measured out for it stages that you might know the number of years and the reckoning. Allah did not create this but in truth. He explains the Ayat (proofs, evidence, verses, lessons, signs, revelations, etc.) in detail for people who have knowledge.

(64) Verily, in the alternation of the night and the day and in all that Allah has created in the heavens and the earth are Ayat (proofs, evidence, verses, lessons, signs, revelations, etc.) for those people who keep their duty to Allah, and fear Him much.

(65) Verily, those who hope not for their meeting with Us, but are pleased and satisfied with the life of the present world, and those who are heedless of Our Ayat (proofs, evidence, verses, lessons, signs, revelations, etc.),

(66) So who does more wrong than he who forges a lie against Allah or denies His Ayat (proofs, evidence, verses, lessons, signs, revelations, etc.)? Surely, the Mujrimun (criminals, sinners, disbelievers and polytheists) will never be successful!

(67) And when We let mankind taste mercy after some adversity has afflicted them, behold! they take to plotting against Our Ayat (proofs, evidence, verses, lessons, signs, revelations, etc.)! Say: "Allah is more Swift in planning!" Certainly, Our Messengers (angels) record all of that which you plot.

(68) Verily, the likeness of (this) worldly life is as the water (rain) which We send down from the sky; so by it arises the intermingled produce of the earth of which men and cattle eat: until when the earth is clad in its adornments and is beautified, and its people think that they have all the powers of disposal over it, Our Command reaches it by night or by day and We make it like a clean-mown harvest, as if it had not flourished yesterday! Thus do We explain the Ayat (proofs, evidence, verses, lessons, signs, revelations, laws, etc.) in detail for the people who reflect.

(69) He it is Who has appointed for you the night that you may rest therein, and the day to make things visible (to you). Verily, in this are Ayat (proofs, evidence, verses, lessons, signs, revelations, etc.) for a people who listen (i.e. those who think deeply).

(70) And recite to them the news of Nuh (Noah). When he said to his people: "O my people, if my stay (with you), and my reminding (you) of the Ayat (proofs, evidence, verses, lessons, signs, revelations, etc.) of Allah is hard on you, then I put my trust in Allah. So devise your plot, you and your partners, and let not your plot be in doubt for you. Then pass your sentence on me and give me no respite.