In this page, we will cover the rules for using parentheses, including when to use them and how to use them correctly. We will provide examples of their usage in different contexts, and offer tips for avoiding common mistakes.
What Are Parentheses?
Parentheses are punctuation marks used to enclose information that:
- adds extra detail
- gives clarification
- provides examples
- includes references or citations
- offers a side note or comment
- is helpful but not required to understand the sentence
They are also known as round brackets, and they appear as:
( )
Here’s a simple example:
-
John (my neighbor) is a great cook.
The phrase my neighbor is extra information added for clarity. The sentence still makes sense without it:
-
John is a great cook.
This is the core idea of parentheses: they allow the writer to add information smoothly, without interrupting the main sentence.
How to Use Parentheses
Parentheses—also called round brackets—are used in English writing to add extra information to a sentence. The information inside them is helpful, but not essential to the main meaning of the sentence.
1. Adding Extra Information
This is the most common use of parentheses. You can include extra details, clarifications, or side notes that are helpful but not essential to the main sentence.
Examples:
- John (my neighbor) is a great cook.
- Sarah bought a new bike (the red one she always wanted).
These parenthetical parts can be removed without changing the basic meaning of the sentence:
- John is a great cook.
- Sarah bought a new bike.
2. Adding Clarifications or Explanations
Parentheses can help explain a term or idea.
Examples:
- He finally got his degree (a goal he had for many years).
- She adopted a Shiba Inu (a Japanese dog breed).
3. Adding Short Translations
When introducing words from another language, parentheses can show translations.
Examples:
- He greeted me with “hola” (hello in Spanish).
- The word “arigatou” (thank you) is common in Japanese.
4. Adding Abbreviations or Acronyms
This is especially common in academic and professional writing.
Examples:
- The World Health Organization (WHO) provides global health guidelines.
- The United States of America (USA) has a diverse culture.
Once the abbreviation is introduced, you can use only the abbreviation in the rest of the text.
5. Adding Citations, Statistics, or Research Notes
Parentheses are widely used in academic writing to show data such as sample size, dates, or references.
Example:
-
Most participants (n = 50) preferred chocolate ice cream.
They can also show author-year citations in some citation styles:
-
Regular exercise improves mental health (Smith, 2020).
6. Adding Dates or Years
Dates often appear inside parentheses to give quick, supporting detail.
Examples:
- She was born in Paris (1994).
- The company was founded in 1982 (over 40 years ago).
7. Adding Afterthoughts or Side Notes
Writers sometimes use parentheses to include comments that feel like personal remarks.
Examples:
- He finally replied to my message (after three days!).
- I’ll meet you at 7 p.m. (if traffic isn’t too bad).
These create a conversational tone.
Parentheses in Different Fields
Parentheses are punctuation marks that are commonly used in writing to enclose additional information that is not essential to the main sentence. In this section, we will explore some of the common uses of parentheses.
Parentheses in Mathematics
In math, parentheses show which operation should happen first.
Examples:
- 2 + (3 × 4) = 14
- (2 + 3) × 4 = 20
They provide structure and prevent confusion.
Parentheses can also show negative numbers:
-
(–5) + 9 = 4
Parentheses in Programming
Programmers use parentheses constantly. Some common uses are:
✔ function calls
✔ grouping expressions
✔ controlling the order of execution
Examples:
- print(“Hello, world!”)
- result = (a + b) × c
Parentheses in Linguistics
In dictionaries or phonetic transcriptions, they may show:
✔ optional sounds
✔ alternative spellings
✔ grammar notes
Example:
-
walk(ed) – “ed” indicates the past tense ending.
Rules for Using Parentheses Correctly
Parentheses follow specific grammar rules. Here are the most important ones.
1. The sentence must still make sense without the parentheses
This is the golden rule.
✔ Correct:
-
The test results (as expected) were positive.
→ Sentence still makes sense: The test results were positive.
✘ Incorrect:
-
(The test results) were positive.
→ Without parentheses: were positive → not a complete sentence.
2. Punctuation Placement
Here is a simple guide:
✔ If the parenthetical text is part of the sentence → final punctuation goes outside.
Example:
-
He loves pizza (especially with extra cheese).
✔ If the entire sentence is inside parentheses → punctuation stays inside the parentheses.
Example:
-
(This is a full sentence.)
✔ Do not double-punctuate.
Example:
✘ He said, “I’m tired.”.
✔ He said, “I’m tired.”
3. Capitalization Inside Parentheses
If the parenthetical starts with a complete sentence, capitalize it.
-
He canceled the meeting. (It was raining heavily.)
If it is just a phrase, do not capitalize.
-
He canceled the meeting (because of the heavy rain).
Types of Parentheses
Many learners confuse parentheses with other types of brackets. Here are the key differences.
Round Brackets (Parentheses) — ( )
Used for extra information in writing.
Example:
-
We will go to the park (if it stops raining).
Square Brackets — [ ]
Used to:
- add clarification inside a quote
- modify or correct quoted text
- show missing text
Example:
-
“She [the manager] approved the request.”
Curly Brackets — { }
Mostly used in:
- programming
- mathematics
- showing sets or choices
Example:
-
Choose a color: {red, blue, green}.
Angle Brackets — < >
Used in:
- coding
- HTML tags
- specialized fields
Example:
-
<p>This is a paragraph</p>
Exercises for Practice
Now that we’ve gone over the basics of using parentheses and brackets, it’s time to put your knowledge to the test with some exercises. Don’t worry, we’ve got the answers for you too!
Exercise 1
Add parentheses or brackets where necessary in the following sentences:
- The cat sat on the mat and licked its paws.
- My favorite colors are blue, green, and yellow.
- The concert, which was sold out, was amazing.
- The teacher gave us a pop quiz today.
Answers:
- The cat sat on the mat (and licked its paws).
- My favorite colors are (blue, green, and yellow).
- The concert (which was sold out) was amazing.
- The teacher gave us a pop quiz today.
Exercise 2
Choose the correct punctuation mark to complete the sentence:
- The weather is nice (, / ; / -) we should go for a walk.
- He is a doctor (, / ; / -) he works at the hospital.
- The book, which was written by J.K. Rowling (, / ; / -) is one of my favorites.
- I need to buy milk, bread, and eggs (, / ; / -) I’m going to the grocery store.
Answers:
- The weather is nice; we should go for a walk.
- He is a doctor; he works at the hospital.
- The book, which was written by J.K. Rowling, is one of my favorites.
- I need to buy milk, bread, and eggs; I’m going to the grocery store.
Exercise 3
Rewrite the following sentences using parentheses or brackets to add extra information:
- The movie was good. It was directed by Steven Spielberg.
- The cake was delicious. It was made by my mom.
- The building is old. It was built in the 1800s.
Answers:
- The movie (directed by Steven Spielberg) was good.
- The cake (made by my mom) was delicious.
- The building (built in the 1800s) is old.
These exercises should help you become more comfortable using parentheses and brackets in your writing. Keep practicing and soon it will become second nature!
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