Negative prefixes worksheet for learning English vocabulary.

Let’s go step by step to solve each problem. We’re looking for the correct negative prefix that changes the meaning of the word to match the description.

We have these prefixes to choose from:
ab, dis, dis, il, im, in, ir, mis, over, un, un, under

(Note: “dis” and “un” appear twice — we can use them more than once if needed.)

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1. not reliable: → We need a prefix that means “not”. The word is “reliable”.
→ “Unreliable” = not reliable ✔
→ Prefix: un

2. not credible: → “Credible” means believable. Not believable = “incredible”? Wait — “incredible” usually means amazing! But in logic, “in-” can mean “not”. Actually, “incredible” *can* mean “not credible”, but it’s often used positively. However, in this context, we want the negative form.
Wait — let’s think again. Is there a better fit?
Actually, “incredible” is the standard negative form of “credible” when meaning “not believable”. But sometimes “uncredible” is used informally. However, in formal English, “incredible” is accepted as “not credible”.
But wait — look at the list: we have “in” as an option. So:
→ “incredible” = not credible ✔
→ Prefix: in

BUT — hold on! Let me double-check common usage. In many textbooks, “incredible” is taught as meaning “amazing”, while “unbelievable” is used for “not credible”. Hmm… maybe I made a mistake.

Wait — actually, “credible” → “incredible” DOES mean “not credible” in its original Latin sense. For example: “His story was incredible” (meaning hard to believe). So yes, it’s correct.

However, let’s check other options. Do we have “un”? Yes. But “uncredible” is not standard. So “in” is correct here.

✔ Prefix: in

3. not probable: → “Probable” means likely. Not likely = “improbable”
→ “Im-” is used before words starting with “p”
→ Prefix: im

4. not honest: → “Honest” → “dishonest”
→ “Dis-” is the prefix here
→ Prefix: dis

5. not legal: → “Legal” → “illegal”
→ “Il-” is used before “l”
→ Prefix: il

6. not responsible: → “Responsible” → “irresponsible”
→ “Ir-” is used before “r”
→ Prefix: ir

7. used cruelly or badly: → This is about misuse. “Misused” = used wrongly or badly
→ Prefix: mis

8. not used anymore: → Something that was used but now isn’t — “unused”? No, that means never used.
Wait — “not used anymore” = no longer in use → “disused”
Example: a disused factory = one that is no longer used
→ Prefix: dis

9. not ever used: → Never used → “unused”
→ Prefix: un

10. used in the wrong way: → Again, “misused” — same as #7?
Wait — #7 was “used cruelly or badly” → also “misused”
But #10 is “used in the wrong way” — still “misused”
Hmm — are they the same? Maybe the worksheet intends different answers?

Wait — let’s re-read:

7. used cruelly or badly → misused
10. used in the wrong way → also misused? That would be duplicate.

But perhaps #10 is meant to be “abused”? But “abused” is stronger — implies harm or cruelty.

Looking back at the prefix list: we have “ab” as an option.

“Abused” = treated badly or cruelly — which matches #7 better?

Wait — let’s clarify:

- “Misused” = used incorrectly or for the wrong purpose
- “Abused” = treated with cruelty or violence; or used excessively/harmfully

So:

#7: “used cruelly or badly” → could be “abused”
#10: “used in the wrong way” → “misused”

That makes more sense!

So:

7. abused → prefix: ab
10. misused → prefix: mis

Yes — that fits better and uses different prefixes.

11. used too much: → “Overused” = used too much
→ Prefix: over

Now let’s list all answers clearly:

1. not reliable → unreliable
2. not credible → incredible
3. not probable → improbable
4. not honest → dishonest
5. not legal → illegal
6. not responsible → irresponsible
7. used cruelly or badly → abused
8. not used anymore → disused
9. not ever used → unused
10. used in the wrong way → misused
11. used too much → overused

Check if we used all prefixes appropriately and didn’t miss any.

Prefixes given: ab, dis, dis, il, im, in, ir, mis, over, un, un, under

We used:
- un (twice: #1 and #9) ✔
- in (#2) ✔
- im (#3) ✔
- dis (twice: #4 and #8) ✔
- il (#5) ✔
- ir (#6) ✔
- ab (#7) ✔
- mis (#10) ✔
- over (#11) ✔

Leftover: “under” — not used. That’s okay — not all prefixes must be used.

All answers make sense.

Final Answer:
1. un
2. in
3. im
4. dis
5. il
6. ir
7. ab
8. dis
9. un
10. mis
11. over