Hyphens are an important part of writing sentences, and often are overlooked. Authorities aren't in100-percent agreement about when you should use a hyphen with a compound modifier and when not to. Make sure you do not confuse a hyphen with a dash and follow the rules of the style guide. To help you with questions that may arise when writing your school assignments, use an authoritative dictionary and an authoritative style guide. Learn to use hyphens correctly in sentences.

Step 1

Link compound modifiers with hyphens. A compound modifier is when two or more words together modify a single noun; link all of the words involved with a hyphen, whether they appear before or after the noun. Example: "A first-rate student" or "the 10-year-old boy." This does not apply to adverbs such as “very” and those adverbs that end in "-ly."

Step 2

Link compound proper nouns and adjectives with a hyphen. For example, "Italian-American."

Step 3

Use a hyphen with numbers and fractions. For example, "four-fifths," "thirty-eight" and so on.

Step 4

Separate double vowels with a hyphen that can sometimes occur with prefixes. The double vowel can sometimes be awkward. For example, "re-elect" or "re-examination."

Step 5

Use hyphens with other words that are prefixes, such as "self-administer" and others.

Step 6

Hyphenate compound words. There are certain words that are always hyphenated, like "water-repellent." Look up the word in a dictionary if you aren't sure. If the word is not hyphenated in the dictionary, then write it as two words.

Step 7

Use a hyphen in any instance in which the meaning of a word might be unclear if you did not use a hyphen. For example, "She likes to read as recreation" versus "The director did an excellent job in the re-creation of the 1940s."