Mayella Ewell takes the witness stand in chapter 18 of To Kill a Mockingbird. Mr. Gilmer, the prosecutor, questions her about the evening she was attacked. Mayella recounts that she was sitting on her porch on the day of the incident when Tom Robinson came by. She asked him to chop up a chifferobe. She then testifies that Tom attacked her. Through tears, she claims that Tom grabbed her around the neck, repeatedly hit her, and threw her to the ground. Mr. Gilmer asks if she called out for help, and she says that she did. She says that Tom "took advantage" of her, meaning that he raped her. Mr. Gilmer asks Mayella if she fought back. Mayella says that she did. She says that the next thing she remembers is her father being there and demanding to know who attacked her.
To the reader and many listeners in the courthouse, this testimony comes off as rehearsed. As a skilled lawyer, Atticus carefully deconstructs Mayella's testimony in his cross-examination. Through his line of questioning, Atticus shows that Mayella's claims are most certainly false and that Tom Robinson could not have committed the crime that he is being accused of.
Although the "facts" that Mayella states during Mr. Gilmer's questioning are false, we do learn some facts about Mayella herself from it. Although her testimony is rehearsed, she still has trouble making it, as her emotions come flowing to the surface. She is scared, which is something that she admits to the judge. Mayella's nervousness shows in the way that she breaks down into tears and in the way she twists her handkerchief "into a sweaty rope."