Hyphens and Dashes
Hyphens Versus Dashes
Hyphens are used to form compound units, e.g., first-rate, and with certain prefixes, e.g., semi-incapacitated.
Dashes are used when writing a range, e.g., 3–5 treatments. Em dashes are used to separate content within a sentence, e.g., a pile of vegetables—topped by an eggplant—caught his eye.
Hyphen or No Hyphen?
Use a hyphen when a compound modifier precedes a noun.
- He is a well-behaved Chihuahua.
Do not use a hyphen when the compound modifier follows a verb, including the verb "to be".
- The Chihuahua is well behaved.
- The Chihuahua appears well behaved.
Don't see your question answered here? CUIMC uses the Associated Press (AP) Stylebook.