Simple grammar worksheet helping students practice forming plural nouns from singular examples like 'pen' and 'butterfly'.

Let's solve the task of converting singular nouns to their plural forms.

We'll go through each noun and apply standard English pluralization rules. Some follow simple rules (add -s or -es), while others have irregular or special forms.

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✔ Rules for Plural Nouns:

1. Most nouns: Add -s
Example: *pen → pens*

2. Nouns ending in -s, -sh, -ch, -x, -z: Add -es
Example: *brush → brushes*

3. Nouns ending in -y:
- If preceded by a consonant, change -y → -ies
Example: *baby → babies*
- If preceded by a vowel, just add -s
Example: *day → days*

4. Nouns ending in -f or -fe: Often change to -ves
Example: *knife → knives*, *leaf → leaves*

5. Irregular plurals:
- *child → children*, *man → men*, *woman → women*, etc.
- *mouse → mice*, *tooth → teeth*, *foot → feet*
- *person → people* (not "persons" in common usage)

6. Some words have the same singular and plural form:
- *sheep*, *deer*, *fish* (in some contexts)

7. Words like "octopus": Can have different plural forms depending on usage:
- octopuses (most common)
- octopi (from Latin, but often considered incorrect)
- octopodes (rare)

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Now let’s fill in the table:

| Singular | Plural | Singular | Plural |
|----------|--------------|-------------|----------------|
| 1. pen | pens | 11. butterfly | butterflies |
| 2. pencil | pencils | 12. photo | photos |
| 3. book | books | 13. video | videos |
| 4. chair | chairs | 14. hand | hands |
| 5. table | tables | 15. eye | eyes |
| 6. window| windows | 16. brush | brushes |
| 7. bed | beds | 17. peach | peaches |
| 8. shoe | shoes | 18. baby | babies |
| 9. bus | buses | 19. candy | candies |
| 10. box | boxes | 20. octopus | octopuses (or octopi) |

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🔍 Explanation for tricky ones:

- Butterfly → butterflies: Ends in -y, preceded by consonant (l) → change -y → -ies
- Photo → photos: Regular plural; ends in -o, but many words ending in -o take -s (e.g., *photo*, *piano*, *radio*)
- Video → videos: Same as above
- Hand → hands: Regular plural
- Eye → eyes: Regular plural
- Brush → brushes: Ends in -sh → add -es
- Peach → peaches: Ends in -ch → add -es
- Baby → babies: Ends in -y, preceded by consonant (b) → change to -ies
- Candy → candies: Ends in -y, preceded by consonant (d) → change to -ies
- Octopus → octopuses: Most widely accepted plural. Though octopi is sometimes used (from Latin root), it's not technically correct since "octopus" is from Greek, not Latin. So octopuses is preferred.

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✔ Final Answer Table:

| Singular | Plural | Singular | Plural |
|----------|--------------|-------------|----------------|
| 1. pen | pens | 11. butterfly | butterflies |
| 2. pencil | pencils | 12. photo | photos |
| 3. book | books | 13. video | videos |
| 4. chair | chairs | 14. hand | hands |
| 5. table | tables | 15. eye | eyes |
| 6. window| windows | 16. brush | brushes |
| 7. bed | beds | 17. peach | peaches |
| 8. shoe | shoes | 18. baby | babies |
| 9. bus | buses | 19. candy | candies |
| 10. box | boxes | 20. octopus | octopuses |

> ✔ All plurals are now correctly formed!

Let me know if you'd like this as a printable version or with explanations for kids!