Which word contains a prefix that changes the meaning: "unhappy"?

Which word contains a prefix that changes the meaning: "unhappy"?

• A. happy
• B. unhappy
• C. kindness
• D. quickness

Answer: (B)

This item tests understanding how prefixes can flip meaning. The word that shows this is unhappy, because it has the prefix un- attached to the base word happy. The prefix un- means “not,” so unhappy means not happy. The other options don’t flip meaning with a prefix. Happy has no prefix at all. Kindness and quickness use the suffix -ness to turn an adjective into a noun (kind → kindness, quick → quickness), which changes part of speech but not the opposite of the base meaning.

This item tests understanding how prefixes can flip meaning. The word that shows this is unhappy, because it has the prefix un- attached to the base word happy. The prefix un- means “not,” so unhappy means not happy.

The other options don’t flip meaning with a prefix. Happy has no prefix at all. Kindness and quickness use the suffix -ness to turn an adjective into a noun (kind → kindness, quick → quickness), which changes part of speech but not the opposite of the base meaning.