Use Hyphens & Dashes Correctly

Use a hyphen with the compound numbers twenty-one through ninety-nine, and with fractions used as adjectives.

• CORRECT: sixty-five students constituted a majority.
• CORRECT: A two-thirds vote was necessary to carry the measure.

Use a hyphen with the prefixes ex, all, and self and with the suffix elect.

• CORRECT: The constitution protects against self-incrimination.
• CORRECT: The president-elect was invited to chair the meeting.

Use a hyphen with a compound adjective when it comes before the word it modifies but not when it comes after the word it modifies.

• CORRECT: The no-holds-barred argument continued into the night.
• CORRECT: The argument continued with no holds barred.

Use a hyphen with any prefix used before a proper noun or adjective.

• CORRECT: His pro-African sentiments were heartily applauded.
• CORRECT: They believed that his activities were un-American.

Use a hyphen to separate component parts of a word in order to avoid confusion with other words or to avoid the use of a double vowel.

• CORRECT: The sculptor was able to re-form the clay after the dog knocked over the bust.
• CORRECT: The family re-entered their house after the marshal departed.

Use a dash to indicate an abrupt change of thought.

• CORRECT: The inheritance must cover the entire cost of the proposal-Gail has no other money to invest.
• CORRECT: To get a high score-and who doesn't want to get a high score?-you need to devote yourself to prolonged and concentrated study.