What passages by Bob Ewell give evidence of his social class?

Bob Ewell represents what is commonly referred to as the stereotype of "white trash": dissolute, irresponsible, lazy, abusive, ignorant, and unreasonable. His actions and reactions, as well as his speech and remarks, evince this stereotype when he is on the witness stand during the trial of Tom Robinson.

Here are passages that depict certain of these stereotypical traits:

• 
  Attitude
  When he is first addressed by the prosecutor, Mr. Gilmer, who asks "Mr. Robert Ewell?" Bob Ewell replies disrespectfully "That's my name, cap'n," causing Mr. Gilmer to bristle. Then, after Mr. Gilmer asks, "Are you the father of Mayella Ewell?" Ewell replies crudely, "Well, if I ain't, I can't do nothing about it now, her ma's dead." At this point Judge Taylor intervenes and repeats the question. This time Bob Ewell answers with meekness, saying "Yes sir" because he knows that he is being impertinent in a court of law. Nevertheless, his lack of respect for the courtroom indicates his crudeness.


• 
  Diction
  When Mr. Gilmer asks Bob Ewell to describe "in your own words" what happened on the night in question, Ewell literally does use his own choice of words:

"Well, ...I was comin' in from the woods with a load o'kindlin' and just as I got to the fence I heard Mayella screamin' like a stuck hog inside the house.... I run up to th'window and I seen...that black n****r yonder ruttin' on my Mayella!"

After this loud and crude exclamation about Tom, Judge Taylor has to hammer his gavel for "fully five minutes." Then, he admonishes Ewell to confine himself to "Christian English usage if that is possible."

• 
  Ignorance
  On cross-examination when Atticus asks Ewell why he did not run for the doctor after he ran inside his house, ran to Mayella, and ran for Sheriff Tate, Bob Ewell replies, "Wadn't no need to. I seen what happened." But Atticus says that he does not understand--"Weren't you concerned with Mayella's condition?

"I most positively was," said Mr. Ewell, who clearly does not understand the question. "I seen who done it."
"No, I mean her physical condition. Did you not think the nature of her injuries warranted immediate medical attention?" Atticus queries. 

Further, in the questioning by Atticus, Bob Ewell does not know what significance there is to his being left-handed, nor does he know the meaning of the word ambidextrous and thereby substantiates the suspicion that Mayella was beaten by him, rather than Tom Robinson, who has a withered left arm because of an accident years ago.

• 
  Irresponsible
  When asked by Atticus why he did not call a doctor for Mayella after she was supposedly raped, he replies that he has never taken his children to a doctor, and "if he had [called a doctor for Mayella], it would have cost him five dollars."
  Early in the narrative, Ewell's lack of responsibility regarding his children is also indicated by his allowing his children to not attend school, and by his spending his welfare money on liquor and his complete neglect of them as they must scour the dump for food and makeshift shoes made from scraps found there. So, his statement about the doctor is in character.