--- title: "The Prefix un-" description: "Spell words using the prefix un- to change meaning; understand that un- creates opposites or reverses actions" canonical: https://lightmysky.com/learn/english/the-prefix-un-mt_zBUcAPDRPM source: https://lightmysky.com/learn/english/the-prefix-un-mt_zBUcAPDRPM.md retrieved: 2026-10-19 --- > **Agent view.** This is the Markdown twin of the page, for tools and assistants. > When to use this site, and the call that answers each job: https://lightmysky.com/agent-instructions.md > API description (OpenAPI 3.1): https://lightmysky.com/openapi.json · Authentication: https://lightmysky.com/auth.md > Pricing: https://lightmysky.com/pricing.md · Catalog: https://lightmysky.com/llms.txt · Full catalog: https://lightmysky.com/llms-full.txt > Every machine-readable file on this domain: https://lightmysky.com/.well-known/ai-catalog.json > Ask for Markdown with `Accept: text/markdown`, a `.md` address, or `?mode=agent`. # The Prefix un- Spell words using the prefix un- to change meaning; understand that un- creates opposites or reverses actions Subject: English · Area: Spelling & Word Study · Ages 5 to 6 Page: https://lightmysky.com/learn/english/the-prefix-un-mt_zBUcAPDRPM ## Ready when they can - Spell words with un- prefix correctly (e.g. 'unhappy', 'unfair', 'undo') - Explain how un- changes the meaning of a word - Create new words by adding un- to known words ## Lesson: The Prefix un- Un- is a small word part called a prefix. It goes at the very front of a word. Adding un- flips a word to mean the opposite. *(drawing: un- joins happy to make unhappy: not happy.)* **Example.** Ben says the game is unfair. He means the game is not fair. Adding un- to fair made a new word. When you spell un- words, keep the whole word the same. Just add the letters u and n to the front. **Recap.** un- goes at the front of a word. It flips the meaning to the opposite. ## Practice 24 questions on this page, each with its working shown. ## Needs first - [Segmenting words into sounds](https://lightmysky.com/learn/english/segmenting-words-into-sounds-mt_BhYJZUsErp) - [Phonics Vocabulary](https://lightmysky.com/learn/english/phonics-vocabulary-mt_EqXlZfB4jp) ## Opens up - [Prefixes (age 7+)](https://lightmysky.com/learn/english/prefixes-age-7-mt_T6nrrf2K43)