Practice your English grammar skills by completing these sentences with the correct prefixes and suffixes.

Let's solve each sentence by adding the correct prefix or suffix to the word in brackets to make a new word that fits the context. We'll use the provided prefixes: DIS-, UN-, IM-, RE-, and suffixes: -ING, -ED, -ANCE, -FUL, -ABLE, -LY, -OUS, -ER.

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1. I can't answer this question. It's ............... (POSSIBLE).

→ "I can't answer" means it's not possible.
Use prefix IM- → IMPOSSIBLE
✔ Answer: impossible

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2. Don't stand near the water. It's too ............... (DANGER).

→ Need an adjective meaning "dangerous". Use suffix -OUS → DANGEROUS
✔ Answer: dangerous

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3. I don't like this fish. It's not very well ............... (COOK).

→ "Not well cooked" – need past participle form. Use suffix -ED → COOKED
✔ Answer: cooked

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4. Kate started crying because she was so ............... (HAPPY)

→ She is sad, so opposite of happy. Use prefix UN- → UNHAPPY
✔ Answer: unhappy

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5. If you have a haircut it will change your ............... (APPEAR)

→ Need a noun form of "appear" → use suffix -ANCE → APPEARANCE
✔ Answer: appearance

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6. Paul never waits in queues. He is too ............... (PATIENT)

→ He doesn't wait, so he lacks patience → use prefix IM- → IMPATIENT
✔ Answer: impatient

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7. Thank you for your advice. You have been very ............... (HELP)

→ Need an adjective meaning helpful → use suffix -FUL → HELPFUL
✔ Answer: helpful

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8. Stealing other people's money is ............... (HONEST)

→ Stealing is dishonest → use prefix DIS- → DISHONEST
✔ Answer: dishonest

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9. Our science ............... is very young. (TEACH)

→ Need a noun for someone who teaches → use suffix -ER → TEACHER
✔ Answer: teacher

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10. Harry didn't think the book was very ............... (INTEREST)

→ Need an adjective describing the book → use suffix -ING → INTERESTING
✔ Answer: interesting

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11. A million pounds was given to the hospital by an ............... person (KNOWN)

→ The person is unknown → use prefix UN- → UNKNOWN
✔ Answer: unknown

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12. When you ............... this paragraph, make it a bit shorter (WRITE)

→ To make something shorter = rewrite → use prefix RE- → REWRITE
✔ Answer: rewrite

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13. Mary was wearing a/an ............... hat (USUAL)

→ Something unusual → use prefix UN- → UNUSUAL
✔ Answer: unusual

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14. That was a great film. It was really ............... (ENJOY)

→ Need an adjective meaning enjoyable → use suffix -ABLE → ENJOYABLE
✔ Answer: enjoyable

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15. I like this town. The people are very ............... (FRIEND)

→ Need an adjective meaning friendly → use suffix -LY → FRIENDLY
✔ Answer: friendly

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16. I don't think you're right. I ............... with you completely (AGREE)

→ Disagree → use prefix DIS- → DISAGREE
✔ Answer: disagree

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✔ Final Answers:

1. impossible
2. dangerous
3. cooked
4. unhappy
5. appearance
6. impatient
7. helpful
8. dishonest
9. teacher
10. interesting
11. unknown
12. rewrite
13. unusual
14. enjoyable
15. friendly
16. disagree

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📌 Explanation Summary:

- Prefixes change the meaning (e.g., *un-* for negation, *dis-* for opposite, *im-* for negative, *re-* for again).
- Suffixes change the part of speech (e.g., *-ing* for present participle, *-ed* for past tense, *-er* for person, *-able* for adjective, *-ly* for adverb, *-ous* for adjective, etc.).

Each word was transformed using appropriate affixes based on grammar and context.