|How to use a period|
|1. Ending a sentence
Periods terminate sentences that are declarative or imperative. There should be one space between the period and the next sentence. Use a period to end a table footnote and a figure legend. If a sentence ends in an abbreviation, only one period is required.
2. In display lines
Display lines—titles of chapters or headings of sections, should not terminate in a period. If a title proceeds content on the same line, a period is used to end the title.
3. In numbered lists
A period should be placed between the number and a single space followed by a capital letter.
4. In reference list
A period ends each reference in a reference list.
5. With quotation marks
A period should be placed before closing quotation marks (single or double).
6. With parentheses and brackets
If a complete sentence that is cited within parentheses or brackets, is independent on other parts, a period should be placed inside the closing mark to end the sentence. If the last part of a sentence is in parentheses, place a period outside the closing mark to terminate the sentence. Only one period is needed in both circumstances.
When a word or phrase is omitted, three dots should be used with a space before and after the three dots. When an entire sentence is omitted, four dots should be placed proceeding a space.
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