

This Grade 4 worksheet introduces students to the power of prefixes — small word parts added to the beginning of a base word to change its meaning. Focusing on two of the most commonly used prefixes in English, re- (meaning again or back) and un- (meaning not or opposite of), this resource helps Class 4 learners build new words, understand their meanings, and use them correctly in sentences through a variety of engaging activities.
Learning prefixes is a key word-building skill for Grade 4 students. Understanding re- and un- is important because:
1. It helps students decode unfamiliar words by breaking them into recognisable parts.
2. It rapidly expands vocabulary by teaching students to build new words from known base words.
3. It strengthens spelling patterns and word structure awareness.
4. It prepares learners for more complex grammar, reading comprehension, and independent writing tasks.
This worksheet includes five well-structured activities that build prefix recognition and correct usage across different sentence contexts:
Exercise 1 – Match the Following
Students match each base word on the left to its correctly prefixed new word from the pool on the right. Base words include do, happy, lock, pack, write, pay, tell, cover, heat, and play, matched to words like redo, unhappy, unlock, unpack, rewrite, repay, retell, discover, reheat, and replay. This activity builds instant recognition of how re- and un- transform base words.
Exercise 2 – Sort the Words
Students sort given word pairs into two groups — Prefix (contains a prefix) and Not Prefix (no prefix involved). Pairs like redo/do, unfair/fair, unlock/lock, repay/pay, retell/tell, discover/cover, reheat/heat, and replay/play go into the Prefix group, while pairs like milk/water, cloud/rain, chair/table, rice/plate, and bus/stop go into the Not Prefix group.
Exercise 3 – Fill in the Blanks
Students select the correct prefixed word from a given pair to complete each sentence. With 10 contextual sentences featuring familiar Indian names like Rahul, Diya, Kartik, Neha, Aarav, and Pooja, this exercise makes learning practical and relatable for Class 4 learners.
Exercise 4 – Multiple Choice Questions
Students choose the correctly prefixed word from four options to answer each question. With 10 questions across two pages, this activity builds both word-building knowledge and exam-style confidence in using prefixes accurately.
Exercise 5 – Sentence Rewriting
Students rewrite 10 given sentences by replacing the incorrect or base word with the correct prefixed word. This task challenges learners to apply their understanding of re- and un- in a meaningful writing context.
Exercise 1 – Match the Following
do → redo
happy → unhappy
lock → unlock
pack → unpack
write → rewrite
pay → repay
tell → retell
cover → discover
heat → reheat
play → replay
Exercise 2 – Sort the Words
Prefix:
redo/do
unfair/fair
unlock/lock
unpack/pack
rewrite/write
repay/pay
retell/tell
discover/cover
reheat/heat
replay/play
Not Prefix:
milk/water
cloud/rain
chair/table
rice/plate
bus/stop
Exercise 3 – Fill in the Blanks
1. redo (redo / do)
2. unhappy (unhappy / happy)
3. unlock (unlock / lock)
4. unpack (unpack / pack)
5. rewrite (rewrite / write)
6. repay (repay / pay)
7. retell (retell / tell)
8. discover (discover / cover)
9. reheat (reheat / heat)
10. replay (replay / play)
Exercise 4 – Multiple Choice Questions
1. d) repack
2. a) unlock
3. c) repay
4. b) redo
5. a) unhappy
6. b) undo
7. d) preview
8. b) retell
9. a) discover
10. c) rewrite
Exercise 5 – Sentence Rewriting
1. Rahul will redo the sum again.
2. Diya was unhappy after a scolding from maam.
3. Kartik will unlock the gate to enter school.
4. Neha will unpack the gift to open it.
5. Aarav will rewrite the essay again.
6. Pooja will repay the money back.
7. Rohan will retell the story to us.
8. Experts discover new facts in the lab.
9. Please reheat the rotis again.
10. Coach will replay the clip again.
Empower your child to build and decode words with confidence in a Free 1:1 English Grammar Trial Class at PlanetSpark — because knowing how words are built is the secret to becoming a stronger reader and writer!
Re- adds the idea of doing something again (e.g., redo), and un- gives the meaning of reversal or negation (e.g., undo).
Prefixes help students decode unfamiliar words and understand their meanings more easily.
Examples include redo, return, undo, and unkind, which can be practiced in various contexts.