When you join two or more words to form a single modifier preceding a noun, add a temporary hyphen: a two-year-old child. If the same words appear after the noun, a hyphen is usually not necessary: the child was two years old. However, some compound modifiers are permanently hyphenated, such as first-class, well-known, part-time, and old-fashioned. Check a dictionary to be sure.

Hyphen Rules to Remember

• Do hyphenate a compound modifier before a noun. (She ran a home-based business.)
• Do hyphenate permanent compounds before or after a noun (The office was old-fashioned.)
• Do not hyphenate combinations including adverbs that end in ly (Our newly decorated offices look great.)
• Do not add hyphens involving prefixes such as non, pre, over, and super (nonabrasive, nonbearing, preseason, overpaid, and supermarket) used before nouns or adjectives.

Directions: Add or delete hyphens as appropriate in the following sentences. Mark "C" at the end of the sentence if a sentence is correct.

1. Managers must revise the company's five year business plan.

2. We sought up to date information from the consultant who was well known for his expertise.

3. Only a highly regarded architect will be considered for the proposed building.

4. All employees participate in on the job training after being hired.

5. Some members of the audience thought the ambassadors address was anti American.

6. The contractor claimed the housing project was three fourths finished.

7. Bruce used his two week vacation to travel to Alaska.

8. Attorneys provided many documents in the pre-trial period of the case.

9. If you follow the step by step instructions, you will have no trouble assembling the bicycle.

10. Most speakers provide a question and answer period after they finish.