How to Use Em Dashes in a Sentence

An em dash signals an abrupt break, adds emphasis, or sets off extra information inside a sentence more strongly than a comma or parenthesis.

What an Em Dash Does in Writing

Writers turn to the em dash when they need to interrupt the main flow or highlight material that deserves attention. It replaces commas for stronger pauses, parentheses for more visible additions, or colons for less formal emphasis. The mark works in pairs to enclose a phrase or stands alone to lead into a final point.

Setting Off Parenthetical Information

Place a pair of em dashes around details that expand on the main clause without breaking its grammar. The enclosed words can be removed and the sentence still makes sense. This approach keeps the added material connected to the main idea rather than tucking it away as parentheses would. Examples include descriptions that contain their own commas or lists that would otherwise confuse readers.

Emphasizing a Word or Phrase

An em dash placed before a final element draws the reader’s eye to a conclusion or surprise. The construction works well for short dramatic statements or when a list precedes an independent clause. It creates more impact than a comma yet stays less formal than a colon.

Marking Breaks or Interruptions

Use a single em dash to show a sudden change in thought or an unfinished statement, especially in dialogue. A second dash closes the interruption if the main sentence resumes. This usage appears often in fiction and casual prose but should stay limited in formal academic work.

Spacing and Typing Rules

Most publishing styles place no spaces on either side of the em dash. In some journalistic contexts a thin space appears on each side. Create the mark by typing two hyphens followed by a word or by using the system shortcut Control+Alt+Minus on Windows.

Common Mistakes to Avoid

Do not combine an em dash with another punctuation mark such as a comma or colon at the same location. Overuse produces a choppy rhythm and weakens cohesion. When the added material is not essential, test whether commas or parentheses would serve the sentence better. Keep the device for moments that truly benefit from extra weight or a clear break.

Comparison With Related Marks

Em dashes differ from en dashes, which connect ranges or compound modifiers, and from hyphens, which join compound words. Parentheses soften added information while commas treat it neutrally. The em dash stands out for its ability to surprise or stress content.

Further guidance appears in resources from the University of Illinois Springfield, the San Francisco Bar Association, Grammarly, and Merriam-Webster.