Word formation worksheet focusing on adding prefixes and suffixes to create correct words.

Here is the completed worksheet with correct answers and explanations.

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## Part 1: Form words adding prefixes and/or suffixes

> Instructions: Use the root word in parentheses to form a new word that fits grammatically and semantically into the sentence.

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✔ 1. _Enthusiasm_ is not enough for achieving one’s goals. (enthusiastic)
→ *Explanation*: “Enthusiastic” is an adjective. The sentence needs a noun as the subject. The noun form of “enthusiastic” is enthusiasm.

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✔ 2. Sugar is _harmful_ to your teeth as it causes decay. (harm)
→ *Explanation*: We need an adjective to describe sugar. Add the suffix -ful → harmful = causing harm.

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✔ 3. Youth are active and _energetic_. (energy)
→ *Explanation*: “Energy” is a noun. We need an adjective to describe youth. Add suffix -etic → energetic.

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✔ 4. Capital _punishment_ is abolished in all European countries. (punish)
→ *Explanation*: “Punish” is a verb. We need a noun. Add suffix -ment → punishment.

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✔ 5. The _government_ is trying to find a solution to _unemployment_. (govern, employ)
→ *Explanation*:
- First blank: “govern” → add suffix -ment → government (the governing body).
- Second blank: “employ” → add prefix un- and suffix -ment → unemployment (lack of jobs).

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✔ 6. This man is doing something _illegal_. Should we call the police? (legal)
→ *Explanation*: “Legal” means allowed by law. Opposite is illegal (add prefix il-).

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✔ 7. Because of a _misunderstanding_, Sarah doesn’t talk to me now. (understand)
→ *Explanation*: “Understand” → add prefix mis- → misunderstanding (a failure to understand).

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✔ 8. Who is the _owner_ of this amazing house? (own)
→ *Explanation*: “Own” is a verb. We need a noun meaning “person who owns”. Add suffix -er → owner.

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✔ 9. The black mamba is the most _poisonous_ snake in the world. (poison)
→ *Explanation*: “Poison” is a noun/verb. We need an adjective to describe the snake. Add suffix -ous → poisonous.

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✔ 10. It was so _thoughtless_ of my neighbours to have an after midnight party. (thought)
→ *Explanation*: “Thought” → add suffix -less → thoughtless (not showing consideration).

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## Part 2: Add the following prefixes to form opposites

> Instructions: Choose the correct prefix from the box (in, un, dis, im, il, ir) to make the opposite of each word.

*(Note: Some words can take more than one prefix, but we choose the most common and correct one.)*

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✔ 1. _illiterate_ — opposite of literate
→ *Prefix*: il- (before “l”) → illiterate

✔ 2. _irrelevant_ — opposite of relevant
→ *Prefix*: ir- (before “r”) → irrelevant

✔ 3. _impolite_ — opposite of polite
→ *Prefix*: im- (before “p”) → impolite

✔ 4. _illegal_ — opposite of legal
→ *Prefix*: il- (before “l”) → illegal

✔ 5. _indirect_ — opposite of direct
→ *Prefix*: in- → indirect

✔ 6. _disadvantage_ — opposite of advantage
→ *Prefix*: dis- → disadvantage

✔ 7. _illogical_ — opposite of logical
→ *Prefix*: il- (before “l”) → illogical

✔ 8. _disloyal_ — opposite of loyal
→ *Prefix*: dis- → disloyal

✔ 9. _innumerable_ — opposite of numerable
→ *Prefix*: in- → innumerable

✔ 10. _incorrect_ — opposite of correct
→ *Prefix*: in- → incorrect

✔ 11. _immoral_ — opposite of moral
→ *Prefix*: im- (before “m”) → immoral

✔ 12. _inactive_ — opposite of active
→ *Prefix*: in- → inactive

✔ 13. _dishonest_ — opposite of honest
→ *Prefix*: dis- → dishonest

✔ 14. _immodest_ — opposite of modest
→ *Prefix*: im- (before “m”) → immodest

✔ 15. _irregular_ — opposite of regular
→ *Prefix*: ir- (before “r”) → irregular

✔ 16. _unsafe_ — opposite of safe
→ *Prefix*: un- → unsafe

✔ 17. _unreal_ — opposite of real
→ *Prefix*: un- → unreal

✔ 18. _imperfect_ — opposite of perfect
→ *Prefix*: im- (before “p”) → imperfect

✔ 19. _irresponsible_ — opposite of responsible
→ *Prefix*: ir- (before “r”) → irresponsible

✔ 20. _unbelievable_ — opposite of believable
→ *Prefix*: un- → unbelievable

✔ 21. _unlucky_ — opposite of lucky
→ *Prefix*: un- → unlucky

✔ 22. _illegible_ — opposite of legible
→ *Prefix*: il- (before “l”) → illegible

✔ 23. _disappear_ — opposite of appear
→ *Prefix*: dis- → disappear

✔ 24. _irrational_ — opposite of rational
→ *Prefix*: ir- (before “r”) → irrational

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## ✔ Final Answer Summary:

Part 1:

1. Enthusiasm
2. Harmful
3. Energetic
4. Punishment
5. Government, unemployment
6. Illegal
7. Misunderstanding
8. Owner
9. Poisonous
10. Thoughtless

Part 2:

1. illiterate
2. irrelevant
3. impolite
4. illegal
5. indirect
6. disadvantage
7. illogical
8. disloyal
9. innumerable
10. incorrect
11. immoral
12. inactive
13. dishonest
14. immodest
15. irregular
16. unsafe
17. unreal
18. imperfect
19. irresponsible
20. unbelievable
21. unlucky
22. illegible
23. disappear
24. irrational

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