Negative Prefixes Worksheet with Exercises

Let’s solve this step by step.

We are working with negative prefixes:
Un-, Ir-, Im-, In-, Il-, Dis-

These prefixes change the meaning of adjectives to their opposites (like “happy” → “unhappy”).

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Part I: Sort the words into correct prefix columns

We have these base adjectives:

> honest, sincere, regular, legal, possible, friendly, capable, patient, logical, expensive, formal, loyal, correct, happy, polite, sensitive, practical, obedient, responsible, comfortable, modest

Now let’s match each one with its correct negative prefix.

#### Un-
Used for many common adjectives:
- unhappy
- uncomfortable
- unfaithful? Wait — we don’t have “faithful”, but we do have “loyal” → disloyal? Actually, “unloyal” is not standard. Let’s check carefully.

Actually, let’s go word by word and assign the right prefix based on standard English usage.

✔ Un-
- unhappy
- uncomfortable
- unfriendly? No — it’s usually “unfriendly” ✔ yes!
- uncapable? No — it’s “incapable”
Wait — better to use known pairs:

Standard negative forms:

| Base Word | Negative Form | Prefix |
|---------------|---------------------|--------|
| honest | dishonest | Dis- |
| sincere | insincere | In- |
| regular | irregular | Ir- |
| legal | illegal | Il- |
| possible | impossible | Im- |
| friendly | unfriendly | Un- |
| capable | incapable | In- |
| patient | impatient | Im- |
| logical | illogical | Il- |
| expensive | inexpensive | In- |
| formal | informal | In- |
| loyal | disloyal | Dis- |
| correct | incorrect | In- |
| happy | unhappy | Un- |
| polite | impolite | Im- |
| sensitive | insensitive | In- |
| practical | impractical | Im- |
| obedient | disobedient | Dis- |
| responsible | irresponsible | Ir- |
| comfortable | uncomfortable | Un- |
| modest | immodest | Im- |

Wait — let’s double-check a few tricky ones:

- “sensitive” → “insensitive” ✔ (In-)
- “expensive” → “inexpensive” ✔ (In-)
- “formal” → “informal” ✔ (In-)
- “correct” → “incorrect” ✔ (In-)
- “modest” → “immodest” ✔ (Im-)
- “obedient” → “disobedient” ✔ (Dis-)
- “responsible” → “irresponsible” ✔ (Ir-)
- “legal” → “illegal” ✔ (Il-)
- “logical” → “illogical” ✔ (Il-)
- “possible” → “impossible” ✔ (Im-)
- “patient” → “impatient” ✔ (Im-)
- “polite” → “impolite” ✔ (Im-)
- “capable” → “incapable” ✔ (In-)
- “sincere” → “insincere” ✔ (In-)
- “honest” → “dishonest” ✔ (Dis-)
- “loyal” → “disloyal” ✔ (Dis-)
- “friendly” → “unfriendly” ✔ (Un-)
- “happy” → “unhappy” ✔ (Un-)
- “comfortable” → “uncomfortable” ✔ (Un-)

So now group them under each prefix column:

#### Un-
- unfriendly
- unhappy
- uncomfortable

#### Ir-
- irregular
- irresponsible

#### Im-
- impossible
- impatient
- impolite
- impractical
- immodest

#### In-
- insincere
- incapable
- inexpensive
- informal
- incorrect
- insensitive

#### Il-
- illegal
- illogical

#### Dis-
- dishonest
- disloyal
- disobedient

Wait — did we miss any?

Original list had 21 words. Let’s count how many we assigned:

Un- : 3
Ir- : 2
Im- : 5
In- : 6
Il- : 2
Dis- : 3
Total = 3+2+5+6+2+3 = 21 ✔ Good.

But wait — “regular” → “irregular” ✔
“responsible” → “irresponsible” ✔
That’s Ir- done.

“possible” → “impossible”
“patient” → “impatient”
“polite” → “impolite”
“practical” → “impractical”
“modest” → “immodest” → that’s 5 for Im- ✔

“In-”:
sincere → insincere
capable → incapable
expensive → inexpensive
formal → informal
correct → incorrect
sensitive → insensitive → that’s 6 ✔

“Il-”:
legal → illegal
logical → illogical → 2 ✔

“Dis-”:
honest → dishonest
loyal → disloyal
obedient → disobedient → 3 ✔

“Un-”:
friendly → unfriendly
happy → unhappy
comfortable → uncomfortable → 3 ✔

Perfect.

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Part II: Write the correct negative adjectives in sentences

We need to fill in blanks using the negative form of the adjective given in the sentence.

1. I suspect he isn’t *honest*. → dishonest
2. Ann doesn’t behave in a *responsible* manner. → irresponsible
3. This arrangement isn’t strictly *legal*. → illegal
4. Nick’s not very *capable*. → incapable
5. This scheme isn’t very *practical*. → impractical
6. It’s not *possible* to do this exercise. → impossible
7. She’s not *happy* here. → unhappy
8. Maybe it’s not *logical*, but... → illogical
9. He was punished for not being *obedient*. → disobedient

All match our earlier assignments.

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Part III: Use one of the adjectives from the box + a negative prefix to complete the sentences

Box of adjectives:

> Sensitive, Expensive, Regular, Formal, Comfortable, Polite, Friendly, Patient, Sincere, Loyal

We must add a negative prefix to one of these to fit each sentence.

Let’s go sentence by sentence.

1. The teacher told his students to learn twenty __________ verbs.
→ Probably “irregular” verbs (common grammar term). “Regular” → “irregular” ✔

2. Mrs. Brown is really __________. She never wants to talk to anyone.
→ Not friendly → “unfriendly” ✔ (from “Friendly”)

3. Susan has no intention of being __________ to his friends.
→ Not loyal → “disloyal” ✔ (from “Loyal”)

4. Adam is so __________. He never wants to explain things twice.
→ Not patient → “impatient” ✔ (but “Patient” is in the box → “impatient”)

Wait — “Patient” is in the box → negative is “impatient”

5. These window locks are __________ and effective.
→ Opposite of “effective”? But we need to pick from box. Maybe “inexpensive”? But “Expensive” is in box → “inexpensive” could work if they’re cheap and effective. Or maybe “uncomfortable”? Doesn’t fit.
Actually, perhaps “insecure”? But not in box.
Wait — maybe “irregular”? No.
Another idea: “These window locks are inexpensive and effective.” That makes sense — cheap but good. So “Expensive” → “inexpensive” ✔

6. John said he was sorry, but they were sure that he was __________.
→ Not sincere → “insincere” ✔ (“Sincere” in box)

7. It is very __________ to tell people you don’t like their clothes.
→ Not polite → “impolite” ✔ (“Polite” in box)

8. These parties are almost always __________; there is no dress code.
→ Not formal → “informal” ✔ (“Formal” in box)

9. They were sitting in a very __________ position.
→ Not comfortable → “uncomfortable” ✔ (“Comfortable” in box)

10. Mr. Black thinks it is very __________ of Tom to think he can do just what he likes.
→ Not loyal? Not really. Not patient? Maybe. But likely “impolite” or “disrespectful” — but we have “Sensitive”? “Insensitive” might fit — thinking only of himself.
“Sensitive” → “insensitive” ✔ Yes — “It is very insensitive of Tom...”

Let’s confirm all:

1. irregular ← Regular
2. unfriendly ← Friendly
3. disloyal ← Loyal
4. impatient ← Patient
5. inexpensive ← Expensive
6. insincere ← Sincere
7. impolite ← Polite
8. informal ← Formal
9. uncomfortable ← Comfortable
10. insensitive ← Sensitive

All use words from the box + correct negative prefix.

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## Final Answer:

Part I: Columns

Un-
unfriendly
unhappy
uncomfortable

Ir-
irregular
irresponsible

Im-
impossible
impatient
impolite
impractical
immodest

In-
insincere
incapable
inexpensive
informal
incorrect
insensitive

Il-
illegal
illogical

Dis-
dishonest
disloyal
disobedient

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Part II: Sentences

1. dishonest
2. irresponsible
3. illegal
4. incapable
5. impractical
6. impossible
7. unhappy
8. illogical
9. disobedient

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Part III: Sentences with boxed words + prefix

1. irregular
2. unfriendly
3. disloyal
4. impatient
5. inexpensive
6. insincere
7. impolite
8. informal
9. uncomfortable
10. insensitive