English grammar is the body of rules that describe the structure of expressions in the English language. This includes the structure of words, phrases, clauses, and sentences. There are historical, social, and regional variations of English. Divergences from the grammar described here occur in some dialects of English. This article describes a generalized present-day Standard English, the form of speech found in types of public discourse including broadcasting, education, entertainment, government, and news reporting, including both formal and informal speech. There are certain differences in grammar between the standard forms of British English, American English, and Australian English, although these are inconspicuous compared with the lexical and pronunciation differences.