Why has Eliza come, and why is she righteously indignant?

In Covent Garden, the Eynsford Hills wait for a cab in the rain. When Freddy goes to hail one, he knocks Liza's flowers out of her basket. She accepts money from Freddy's mother, then Colonel Pickering. A bystander warns her that a man is writing down what she is saying, and she confronts him, saying that she has done nothing wrong. Higgins amazes the crowd by imitating her accent and guessing where they all come from. Pickering and Higgins meet and agree to have dinner, and Higgins fills Liza's basket with money before he leaves. Liza leaves in a cab.

The next day, Liza intrudes upon Pickering and Higgins in Higgins's home. She wants English lessons, and Pickering bets that Higgins could not pass her off as a lady at the ambassador's ball in a month's time. Mrs. Pearce takes Liza away to bathe her and dress her more appropriately, and Liza's father arrives and demands some payment. Higgins likes him and gives him five pounds.