Comma long sentences for clarity; however, this usage is regarded as an error in modern times. The comma and the quotation mark pairing can be used in several ways. In American English, the comma is commonly included inside a quotation mark: In Great Britain and many other parts of the world, punctuation is usually placed within quotation marks only if it is part of what is being quoted or referred to: There is also some difference regarding the use of the serial comma, which is an optional comma placed before the coordinating conjunction in a list of three or more items:
Serial comma Serial comma In English language punctuation, a serial comma or series comma (also called an Oxford comma or a Harvard comma) is a comma placed immediately before the coordinating conjunction (usually "and" or "or") in a series of three or more terms. For example, a list of three countries might be punctuated either as "France, Italy,and Spain" (with the serial comma), or as "France, Italyand Spain" (without the serial comma). Opinions among writers and editors differ on whether to use the serial comma, and usage also differs somewhat between regional varieties of English. In American English, not using a serial