This worksheet helps students practice forming new words by adding the prefix 'un-' to common base words.

Let's solve the problem step by step.

The task is to add the prefix "un-" to each base word to form a new word. The prefix "un-" typically means "not" or "opposite of," so we're creating words that mean the opposite of the base word.

Here are the pairs:

1. un + fair = unfair
→ "Unfair" means not fair.

2. un + afraid = unafraid
→ "Unafraid" means not afraid.

3. un + lucky = unlucky
→ "Unlucky" means not lucky.

4. un + safe = unsafe
→ "Unsafe" means not safe.

5. un + usual = unusual
→ "Unusual" means not usual (i.e., strange or rare).

6. un + true = untrue
→ "Untrue" means not true.

7. un + finished = unfinished
→ "Unfinished" means not finished.

8. un + expected = unexpected
→ "Unexpected" means not expected.

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Final Answers:

1. unfair
2. unafraid
3. unlucky
4. unsafe
5. unusual
6. untrue
7. unfinished
8. unexpected

✔ All these are valid English words formed by adding the prefix "un-" to the base words.