What Are Periods?
Periods are one of the most fundamental punctuation marks in the English language. While they may seem simple, their correct use is essential for clarity, structure, and readability. A period (.) is used to indicate the end of a sentence or an abbreviation. It signals a full stop, providing closure to an idea or thought. Periods help structure writing, making it easier to read and understand. Without them, sentences would run together, causing confusion. They can also be used in ways that break traditional grammar rules for rhetorical purposes.
Examples:
- “She walked to the store.”
- “The experiment was successful.”
Learn Next: How to Use Question Marks
The Four Ways to Use Periods
Periods are commonly used in four ways, each of which is described below with examples:
- Complete a Statement
- End a Fragment
- Create Abbreviations
- Identify Acronyms
1. Complete a Statement
The most common use of a period is to mark the end of a complete sentence. A complete sentence must have a subject and a verb, forming an independent clause.
Examples:
- “The sky turned a brilliant shade of orange.”
- “We should leave now.”
What NOT to Do:
- “We should leave now” (A missing period makes it unclear that the sentence has ended.)
2. End a Fragment
While periods usually end full sentences, they can also be used to end sentence fragments when used deliberately for stylistic effect. Sentence fragments are incomplete thoughts that lack a subject or a verb but can still convey meaning in writing.
Examples:
- “So unfair. So frustrating.” (Emphasizes strong emotion.)
- “A mistake. A huge mistake.” (Creates a dramatic pause.)
What NOT to Do:
- “She went to the store. And bought apples.” (This fragment is not intentional; it should be rewritten as one sentence: “She went to the store and bought apples.”)
3. Create Abbreviations
Periods are used in abbreviations to indicate shortened forms of words. Some abbreviations require periods, while others do not, depending on style guides.
Examples:
- “Dr. Smith is an expert in neuroscience.”
- “The package arrived at 10 a.m.”
What NOT to Do:
- “Dr Smith is an expert in neuroscience” (Missing period in “Dr.” makes the abbreviation incomplete.)
4. Identify Acronyms
Some acronyms use periods between letters, while others do not. This depends on the organization’s preference or style guide being followed.
Examples:
- “The U.S.A. is a large country.” (Periods used in U.S.A.)
- “She works for the F.B.I.” (Some style guides use periods in “F.B.I.”)
What NOT to Do:
- “She works for the FBI.” (This is correct in modern usage, but some styles still use “F.B.I.”)
Rhetorical Use of Periods
While periods traditionally indicate a full stop, breaking the rules can create rhetorical impact in creative or persuasive writing. Writers sometimes use periods deliberately to control pacing, create tension, or emphasize key points.
When Breaking the Rules Makes Sense:
- For Emphasis
- “This. Is. Not. A. Drill.” (Creates a sense of urgency.)
- For a Dramatic Pause
- “She knew exactly what had to be done. But still. She hesitated.” (Slows the pacing for dramatic effect.)
What NOT to Do:
- “He is a great. Writer.” (This break is unnecessary and makes the sentence awkward.)
*Content on this page was curated and edited by expert humans with the creative assistance of AI.