8th grade - Prefix and Suffix worksheet - Free Printable

Let’s go through each sentence one by one. We’ll look at the word in brackets and decide whether to add a prefix (like DIS-, UN-, IM-, RE-) or a suffix (like -ING, -ED, -ANCE, -FUL, -ABLE, -LY, -OUS, -ER) to make it fit the sentence correctly.

We want the new word to make sense in the sentence — both grammatically and logically.

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1. I can’t answer this question. It’s ____________ (POSSIBLE).
→ “Can’t” means not able → so we need the opposite of possible → impossible

2. Don’t stand near the water. It’s too ____________. (DANGER)
→ We need an adjective to describe the water → danger + ous = dangerous

3. I don’t like this fish. It’s not very well ____________. (COOK)
→ We’re talking about how the fish was prepared → cook + ed = cooked

4. Kate started crying because she was so ____________. (HAPPY)
→ Crying usually means sad → so we need the opposite of happy → un + happy = unhappy

5. If you have a haircut it will change your ____________. (APPEAR)
→ We need a noun meaning “how you look” → appear + ance = appearance

6. Paul never waits in queues. He is too ____________. (PATIENT)
→ Not waiting = not patient → im + patient = impatient

7. Thank you for your advice. You have been very ____________. (HELP)
→ We need an adjective meaning “gave help” → help + ful = helpful

8. Stealing other people’s money is ____________. (HONEST)
→ Stealing is wrong → not honest → dis + honest = dishonest

9. Our science ____________ is very young. (TEACH)
→ We need a person who teaches → teach + er = teacher

10. Harry didn’t think the book was very ____________. (INTEREST)
→ He didn’t like it → not interesting → un + interested? Wait — actually, we say “not interesting” → interest + ing = interesting
But note: “didn’t think... very interesting” → yes, that works. So interesting

Wait — let’s double-check: “Harry didn’t think the book was very interesting.” That makes sense. So suffix -ing → interesting

11. A million pounds was given to the hospital by an ____________ person (KNOWN)
→ Someone famous → known + ous = famous? Wait — no, the root is “known”.
Actually, “known” + ly? No.
Better: “well-known” but that’s two words.
Wait — maybe “unknown”? But that would mean not known — doesn’t fit with giving money.
Actually, the correct form is “a well-known person” — but since we must use only prefixes/suffixes from the list…
Looking again: “an ____________ person (KNOWN)”
Perhaps they want “unknown”? But that contradicts the context.
Wait — maybe it’s “renowned”? But that’s not from “known” with simple affix.
Hold on — perhaps it’s “known” + ly? “Knowingly”? Doesn’t fit.
Actually, I think there might be a mistake here — but let’s think:
If someone gives a million pounds, they are likely famous → so “well-known” — but we can’t use “well”.
Alternative: maybe “notable”? Not from “known”.
Wait — perhaps it’s “unknown” — but that would be strange.
Let me check standard usage:
Actually, in many textbooks, this is “an unknown person” — meaning anonymous donor.
Yes! That makes sense — sometimes rich people give anonymously.
So: un + known = unknown

12. When you ____________ this paragraph, make it a bit shorter (WRITE)
→ You are doing the action now or generally → write + e? Or re-write?
“Rewrite” means write again — which fits “make it shorter” → so re + write = rewrite

13. Mary was wearing a/an ____________ hat (USUAL)
→ Probably means not usual → un + usual = unusual

14. That was a great film. It was really ____________. (ENJOY)
→ We felt enjoyment → enjoy + able = enjoyable

15. I like this town. The people are very ____________. (FRIEND)
→ Friendly people → friend + ly = friendly

16. I don’t think you’re right. I ____________ with you completely (AGREE)
→ Don’t agree → dis + agree = disagree

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Now let’s list all answers clearly:

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

Final Answer:
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