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

(91) And who does more wrong than he who is reminded of the Ayat (proofs, evidence, verses, lessons, signs, revelations, etc.) of his Lord, but turns away from them, forgetting what (deeds) his hands have sent forth. Truly, We have set veils over their hearts lest they should understand this (the Qur'an), and in their ears, deafness. And if you (O Muhammad صلى الله عليه وسلم) call them to guidance, even then they will never be guided.

(92) "They are those who deny the Ayat (proofs, evidence, verses, lessons, signs, revelations, etc.) of their Lord and the Meeting with Him (in the Hereafter). So their works are in vain, and on the Day of Resurrection, We shall assign no weight for them.

(93) "That shall be their recompense, Hell; because they disbelieved and took My Ayat (proofs, evidence, verses, lessons, signs, revelations, etc.) and My Messengers by way of jest and mockery.

(94) "Go you and your brother with My Ayat (proofs, evidence, verses, lessons, signs, revelations, etc.), and do not, you both, slacken and become weak in My Remembrance.

(95) And thus We have sent it down as a Qur'an in Arabic, and have explained therein in detail the warnings, in order that they may fear Allah, or that it may cause them to have a lesson from it (or to have the honour for believing and acting on its teachings).

(96) (Allah) will say: "Like this: Our Ayat (proofs, evidence, verses, lessons, signs, revelations, etc.) came unto you, but you disregarded them (i.e. you left them, did not think deeply in them, and you turned away from them), and so this Day, you will be neglected (in the Hell-fire, away from Allah's Mercy)."

(97) And thus do We requite him who transgresses beyond bounds [i.e. commits the great sins and disobeys his Lord (Allah) and believes not in His Messengers, and His revealed Books, like this Qur'an], and believes not in the Ayat (proofs, evidence, verses, lessons, signs, revelations, etc.) of his Lord; and the torment of the Hereafter is far more severe and more lasting.

(98) And if We had destroyed them with a torment before this (i.e. Messenger Muhammad صلى الله عليه وسلم and the Qur'an), they would surely have said: "Our Lord! If only You had sent us a Messenger, we should certainly have followed Your Ayat (proofs, evidence, verses, lessons, signs, revelations, etc.), before we were humiliated and disgraced."

(99) Man is created of haste. I will show you My Ayat (torments, proofs, evidence, verses, lessons, signs, revelations, etc.). So ask Me not to hasten (them).

(100) We helped him against the people who denied Our Ayat (proofs, evidence, verses, lessons, signs, revelations, etc.). Verily, they were a people given to evil. So We drowned them all.