My Fair Lady is a 1956 musical theater production with lyrics and book by Alan Jay Lerner and music by Frederic Loewe, adapted from George Bernard Shaw's Pygmalion. It was also made into a film by Warner Bros. in 1964.
Henry Higgins, an arrogant, irascible professor of phonetics, finds an impoverished young woman, Eliza Doolittle, selling flowers, and boasts to a new acquaintance, Colonel Pickering, that he can train her to speak so "properly" that he could pass her off as a duchess. Eliza finds her way to the professor's house and offers to pay the professor to give her elocution lessons so that she can get a better job. A wager is made with Colonel Pickering that Higgins cannot achieve this and he takes her on as a challenge of his skills free of charge.
Eliza's father, a dustman, arrives weeks later to reclaim his daughter, or at least some compensation for her loss, and is paid off. Higgins is impressed by the man's genuineness and natural gift for language, contrasting with his total lack of moral values ("Can't afford 'em!")
At first Eliza makes no progress, but just as she thinks the idea is hopeless she tries one more time, suddenly "gets it", and begins to talk with an impeccable upper class English accent. Higgins takes her on her first public appearance at Ascot Racecourse where she makes a good impression with her polite manners, only to shock everyone by a sudden and vulgar lapse into ****ney. Higgins, who dislikes the pretentiousness of these upper class people, partly conceals a grin behind his hand, as if to convey the message to the audience, "I wish I had said that!"
The bet depends on Eliza's passing as a lady at the 'embassy ball', which she does successfully despite the presence of a Hungarian phonetics expert, who is completely taken in. Higgins's ungrateful treatment of her after this success leads Eliza to walk out on him, leaving the seemingly clueless Higgins mystified by her ingratitude.
The ending of the musical was subtly changed from that of the play, in order to please audiences by a suggestion of budding romance between Eliza and Higgins. A contemporary version of the Pygmalion motif can be found in Willy Russell's play Educating Rita (1980).
To translate that into words you can understand, Nathan is challenging me to turn you into someone whose posts look respectable and don't scream "badly written so not worth reading" the moment you look at them.