What is the author's style in Vengeful Creditor by Chinua Achebe?

One of the ways in which Achebe indicates the deep class divisions in his story is through the use of dialect. The Emenikes speech is depicted as standard English, while the poor speak a dialect that combines elements of their native language and English. Martha, who has been educated, is the exception. Although desperately poor, she uses the language taught to her by the white missionaries. Her daughter Veronica is fluent in both, as is the supermarket clerk, who speaks one way to Mrs. Emenike and another to John, the bag boy. Mr. Emenike, too, seems to be bilingual, using native dialect when he grills the servants, but also when he speaks of Mike Ogudu, whose position is superior to his own. "Too much money is bad-o," he tells his wife, referring to his rich friend.