The primary rule for periods is to use them to end declarative sentences.
Here's a more detailed breakdown of the rules governing periods:
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Ending Declarative Sentences: Periods are used to mark the end of a statement or declaration.
- Example: The dog is sleeping.
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Abbreviations: Periods are often used in abbreviations, although their use is becoming less common, particularly in acronyms.
- Example: Mr. Mrs. Dr.
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Ellipsis: Three periods (...) indicate omitted words in a quote or a pause in speech or thought.
- Example: "I wasn't sure... but I decided to go anyway."
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Separating Elements in Reference Lists: In some citation styles, periods are used to separate different elements in a bibliography or reference list.
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Placement after other Punctuation: Generally, a period follows other punctuation marks like quotation marks or parentheses when the punctuated element is at the end of the sentence.
- Example: She said, "I'm going home now."
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Spacing After a Period: Use only one space after a period at the end of a sentence. This is the modern style, replacing the outdated practice of using two spaces.
In summary, use a period to end a complete declarative sentence, with only one space following the period to the next sentence. Periods also have other specialized uses within writing.
