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Prefixes Change What a Word Means · Word Building · CCSS.ELA-LITERACY.L.3.4.B · prefixes

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Prefixes Change What a Word Means

with Quill

A cozy library workshop where Quill, a cheerful owl with a feathered quill pen tucked behind one ear, stands at a big chalkboard. She uses magnetic letter tiles to snap prefixes onto the front of root words, watching the meaning flip like a switch — then grins wide as the new word lights up.

Explain what a prefix is and where it attaches to a word.
Identify how adding un- changes a word to mean the opposite or 'not.'
Identify how adding re- changes a word to mean doing something again.
Predict the meaning of an unfamiliar word by recognizing its prefix.
Compare two words that share a root but have different prefixes.

Key terms

prefix: a word part added to the front
root word: the base word before any change
un-: a prefix that means not
re-: a prefix that means again

Build With Prefixes

A prefix is a tiny word part you snap onto the front of a word. It is like clicking a new block onto a tower. When you add a prefix, the word gets a brand new meaning. The cool part is that prefixes work the same way every time. So once you learn one prefix, you can understand lots and lots of new words all by yourself.

Meet Un And Re

Two super helpful prefixes are un- and re-. The prefix un- means not or the opposite. So happy turns into unhappy, which means not happy. The prefix re- means again. So read turns into reread, which means read again. When you see a new word, look for these prefixes at the front. They give you a big clue about what the whole word means.

Worked examples

What does the word repaint mean

Find the prefix at the front: re-.
Remember re- means again.
Add it to paint: paint again.

Answer: repaint means paint again

Hi there! I'm Quill, and I love building new words — like snapping building blocks together. A prefix is a small word part you attach to the FRONT of a word. It changes the word's meaning in a predictable way. That means once you know what a prefix means, you can figure out hundreds of new words! Let's look at two super-useful prefixes: un- means 'NOT' or 'the opposite of.' Watch: happy → unhappy (not happy). Lock → unlock (the opposite of lock). Tie → untie (the opposite of tying something up). See how the meaning flips? Sometimes un- negates a describing word ('not happy'), and sometimes it reverses an action ('undo a knot') — but it always works against the root word's meaning. re- means 'again.' Watch: read → reread (read again). Build → rebuild (build again). Fill → refill (fill again). Notice that re- always attaches to a doing word — a word that names an action. Ready to build some words? If you get stuck during the activity, look at the root word first — it tells you the base meaning before the prefix changes it. That one step will almost always unlock the answer! Ready to snap some prefixes into place?

Activity

Drag the correct prefix tile onto each root word to match its meaning.

Practice

Add un- or re- to each root word to make a new word.

Match each new word to the meaning that fits it.

Common mistakes to avoid

Un and re mean the sameUn- means not, but re- means again, so they are different.

Check your understanding

Your friend says she needs to 'repack' her backpack before the trip. What does repack most likely mean?

Which word means 'not lucky'?

A student thinks 'reread' and 'unread' mean the same thing because they both have the word 'read' in them. Is the student correct?

Recap

A prefix is a small word part you add to the front of a word to change its meaning. The prefix un- means not, and the prefix re- means again. Learn a prefix once and unlock many new words!

Reflect

What new word did you build with a prefix?