Is today's language at an all-time low? Are pronunciations like cawfee and chawklit bad English? Is slang like my bad or hook up improper? Is it incorrect to mix English and Spanish, as in Yo quiero Taco Bell? Can you write Who do you trust? rather than Whom do you trust? Linguist Edwin Battistella takes a hard look at traditional notions of bad language, arguing that they are often based in sterile conventionality.

Examining grammar and style, cursing, slang, and political correctness, regional and ethnic dialects, and foreign accents and...