When using quotation marks, people are faced with several choices as to how to place punctuation like commas and periods. If you’re writing with British standards, commas, periods, question marks and others fall naturally. Some are included within the quotation marks, if it makes sense, and other are outside of it. The standard rule in American punctuation is that periods go inside quotation marks, as do most commas, even if the punctuation is not part of the quote.
American English is known for its exceptions to rules, and there is one type of incidence where it would not be the case that periods go inside quotation marks. If you place quotation marks around a letter or number, usually the period or comma falls outside the quotes. Consider the following example:
This is the only incidence that ignores the fact that most periods go inside quotation marks. The letter in quotes stands alone.
In most other incidences, though, you’ll find periods go inside and so do commas. Even if you’re quoting a couple of words from a text, commas, without being part of the text are included in the quotes:
Note the commas, though they probably are not part of the original quote. In British English, these would fall outside the quotes.
While you can stand by the rule that most periods and commas go inside the quotation marks if you’re writing in American English, there are different rules for other types of punctuation. Question marks produce their own questions. A question mark can reside outside quotation marks if it is not part of the quote in a sentence that is in the form of a question:
Moreover, unless you are quoting something that contains a semi-colon, this too will fall outside quotation marks.
Don’t forget that, when you’re using longer quotes in the block-indentation style of quoting, you don’t use quotation marks at all. If you quote four or more lines of text, tab in ten spaces for the whole quote and do not use quotation marks. Moreover, if you’re double spacing most of your essay, you may need to single space block-indented quotes. Check with your teacher to see which method he or she prefers.