Home | Grammar Lessons | Grammar Tests | Common Grammar Errors | Grammatical Terms | Easily Confused Words | Search

Follow us on Twitter Use our gadget on iGoogle Follow us on Facebook Chat about grammar Search this site

Using Round and Square Brackets

Round brackets () are used to insert additional information. Square brackets [] are usually used to make a quoted text more understandable.

Round Brackets for Additional Information

Round brackets are used to insert additional information in text. If you were to remove the brackets and the information inside, the text would still work. For example:

Set in the 17th century, The Three Musketeers ("Les Trois Mousquetaires" in French) is a novel by Alexandre Dumas.

Although they are relatively common off Australia, California, South Africa and Mexico, great white sharks usually inhabit coastal waters where the water temperature ranges 12-24 degrees Celsius. They generally hunt by detecting the electrical fields (They can detect less than one billionth of a volt.) emitted by the movements of their prey.

Round Brackets to Denote Singular or Plural

For brevity, round brackets can be used to show that a word could be either singular or plural. For example:

Please write the name(s) of your guest(s) in the section below.

Ensure the rod(s) is(are) aligned with the top section.

Square Brackets to Make the Text Clearer

Square brackets are used to add information that explains the text it follows. (The information is usually added by someone other than the original author.) For example:

Hedy Lamarr once said: "Most people save all their lives and leave it [their money] to somebody else."

"It [electricity] is really just organized lightning."

Square Brackets to Modify the Original Text

Often, square brackets are used to replace text in a quote to make the quote clearer for the reader. For example:

Hedy Lamarr once said: "Most people save all their lives and leave [their money] to somebody else."

Alice Cooper famously said that "from the moment [he] leave[s] [his] house or hotel room, the public owns [him]."

Square Brackets: [sic]

The term "[sic]" is used to show that the word it follows featured in the original text. Often, "[sic]" is used to indicate that a grammar error in the text was written by the original author. For example:

The minister believed that his statement was "appropriate and did not undermine the moral [sic] of our
(should be "morale" not "moral")

Your demand for a "full compliment [sic] of men" cannot be met at this time.
(should be "complement" not "compliment")

Square Brackets: [...]

Ellipsis is used to show text omitted from a quote. Ellipsis is usually written "..." or "[...]". For example:

It's no small irony that the government [...] ends up promoting precisely that which they would most like to repress.
(The ellipsis replaces "inevitably and invariably".)

Andy Warhol is the only genius...with an IQ of 60.
(The ellipsis replaces the words "I've ever known" in this Gore Vidal quote.)
grammar tips

Using lots of brackets in your writing is usually a sign of bad sentence structure. Brackets also look a little informal in serious correspondence. Luckily, the latter issue is easily solved. You don't have to use brackets all the time. In fact, you have choice between round brackets, commas and dashes. These are all called parentheses. The information between the parentheses is called a parenthesis.


Parenthesis is used to add additional information. As such, it is often just a few words, but it can be a complete sentence or even a few sentences. (If it's any longer than that, you should probably reconsider whether it's appropriate as a parenthesis.) If your parenthesis is a complete sentence, it should start with a capital and end in a full stop (period ), which would be inside the parentheses.

See also:

Brackets, commas and dashes - a choice of parentheses

We need your help to improve Grammar Monster.

Do you disagree with something on this site?
Do you have any entertaining examples that would improve this site?
Do you have any pictures that would make our site more entertaining?

  Please tell us
  using this form.

Do you have a grammar question?

  You can ask us
  on our grammar forum.

Share this page with others.

Stuff you might have missed.

Our Top 50 Punctuation Errors
Our Gallery of Favourite/Favorite Grammar Mistakes
Grammar Mistakes Listed by Their Ability to Make You Look Stupid
Our book!
Grammar Lessons | Grammar Tests | Common Grammar Errors | Grammatical Terms | Easily Confused Words | Free Grammar Checker | Search | Contact Us