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Common Core ELA3rd GradeFoundational Skills

RF.3.3: Prefixes, Suffixes and Longer Words

Also written as CCSS.ELA-LITERACY.RF.3.3 · Cluster: Phonics and Word Recognition.

Make a Spelling SheetAll 42 3rd Grade ELA Standards

The Official Wording

Know and apply grade-level phonics and word analysis skills in decoding words.

Common Core State Standards, Grade 3, Reading: Foundational Skills · Read it at the source · Checked October 14, 2026

What RF.3.3 Means in Plain English

Third graders read longer words by spotting parts they know: prefixes like mis- and re-, suffixes like -able and -tion, then the syllables in between. They know what the common parts mean, and they read tricky words like laugh and thought, whose spellings break the rules.

In 2nd grade (RF.2.3) students decoded two-syllable words and words with common prefixes and suffixes. Third grade adds the meaning of those parts and Latin suffixes. In 4th grade (RF.4.3) students combine sounds, syllables, roots and affixes to read any long word.

RF.3.3 I Can Statements

  • I can tell what common prefixes and suffixes mean.
  • I can read a long word by breaking it into parts.
  • I can read tricky words like laugh and thought by sight.

RF.3.3 Worked Example

One sentence with every lettered part of the standard in it: a prefix, two Latin suffixes, long words and two rule-breakers.

Problem

Read this sentence aloud: “Everyone thought the misprinted invitation was laughable.”

Reading misprinted, invitation and laughable
  1. Three words are long, so I don’t guess. I look for parts I know at the front and the end of each one.misprinted · invitation · laughable
  2. Misprinted starts with the prefix mis-, which means wrongly, and ends with -ed. The base word in the middle is print.mis + print + ed = printed wrongly
  3. Invitation ends in -tion, a Latin suffix that says “shun.” Then I clap the rest into syllables.in · vi · ta · tion
  4. Laughable ends in -able, another Latin suffix, which means can be. The base is laugh, a tricky word where augh says /af/, so I know it by sight.laugh + able = can be laughed at
  5. Thought is tricky too. Its ough says /aw/, like in bought, so I read it as a whole word.thought: ough = /aw/
  6. Now I read the whole sentence and check that it makes sense.The invitation was printed wrong, and it was so silly that everyone laughed.
AnswerEveryone thought the mis · print · ed in · vi · ta · tion was laugh · a · ble: the invitation had printing mistakes, and people found it funny.

Check it: Ask the reader what the invitation was like. If they say it was printed wrong and funny, they decoded the words and know what the parts mean.

Common Mistakes with RF.3.3

Sounding out -tion letter by letter

Reads invitation as “in-vi-ta-tee-on”

Try this: Teach -tion, -sion and -able as single chunks on cards, and drill them until students say “shun” and “uh-bul” instantly.

Reading a prefix without its meaning

Reads misprinted correctly but can’t say what it means

Try this: After decoding, ask what the prefix adds: mis- means wrongly, re- means again, un- means not. Then restate the word.

Sounding out tricky words

Reads laugh to rhyme with cow

Try this: Keep a class wall of rule-breakers like laugh, thought and enough, and practice them as whole words in sentences every day.

Where RF.3.3 Fits

Comes BeforeRF.2.3Decode two-syllable words and words with common prefixes and suffixes.
AlongsideL.3.4Use a known prefix or suffix, like pre in preheat, to work out a new word’s meaning.L.3.2Spell words correctly when adding suffixes, like happiness and cries.
Comes NextRF.4.3Use sounds, syllables, roots and affixes to read unfamiliar long words.

Practice RF.3.3

Spelling Worksheet GeneratorFree ToolBuild a week’s list around one suffix, like -able or -tion, so students read and spell the same chunk in every word.Suffix: -ableSuffix: -tionGrade 3
Make a Worksheet
Vocabulary Worksheet GeneratorFree ToolList words that share a prefix, like mis- or re-, and have students split each one before writing what it means.Prefix: mis-Prefix: re-
Make a Worksheet

Quick Check

  1. What does the prefix mis- mean in misprinted?
  2. Split invitation into syllables.
  3. Which two words in the sentence break the usual spelling rules?

RF.3.3: Other Names

RF.3.3CCSS.ELA-LITERACY.RF.3.3

Common Core State Standards © Copyright 2010. National Governors Association Center for Best Practices and Council of Chief State School Officers. All rights reserved. Official wording from the Common Core State Standards PDFs at corestandards.org, last checked October 14, 2026. The explanation, I can statements, example, mistakes and practice on this page are EMStudio’s own, written beside the official wording. They are not part of the standard.