Plural noun formation worksheet focusing on changing 'y' to 'i' before adding 'es'.

Problem Overview:

The task involves applying the plural rule for words ending in "y" preceded by a consonant. The rule states:
- If a word ends in "y" and is preceded by a consonant, change the "y" to "i" and add "es" to form the plural.
- If the "y" is preceded by a vowel, simply add "s" to form the plural.

We need to:
1. Apply this rule to the given singular words to form their plurals.
2. Write sentences using the plural forms of specific words.

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Step-by-Step Solution:

#### Part 1: Forming Plurals
We will analyze each word to determine whether it follows the rule or not.

1. cherry
- Singular: cherry
- Rule: The "y" is preceded by a consonant ("r").
- Change "y" to "i" and add "es": cherries

2. pony
- Singular: pony
- Rule: The "y" is preceded by a consonant ("n").
- Change "y" to "i" and add "es": ponies

3. story
- Singular: story
- Rule: The "y" is preceded by a consonant ("r").
- Change "y" to "i" and add "es": stories

4. berry
- Singular: berry
- Rule: The "y" is preceded by a consonant ("r").
- Change "y" to "i" and add "es": berries

5. puppy
- Singular: puppy
- Rule: The "y" is preceded by a consonant ("p").
- Change "y" to "i" and add "es": puppies

6. lady
- Singular: lady
- Rule: The "y" is preceded by a consonant ("d").
- Change "y" to "i" and add "es": ladies

7. boy
- Singular: boy
- Rule: The "y" is preceded by a consonant ("b").
- Change "y" to "i" and add "es": boys

8. trolley
- Singular: trolley
- Rule: The "y" is preceded by a consonant ("l").
- Change "y" to "i" and add "es": trolleys

9. key
- Singular: key
- Rule: The "y" is preceded by a consonant ("k").
- Change "y" to "i" and add "es": keys

10. monkey
- Singular: monkey
- Rule: The "y" is preceded by a consonant ("k").
- Change "y" to "i" and add "es": monkeys

11. spy
- Singular: spy
- Rule: The "y" is preceded by a consonant ("p").
- Change "y" to "i" and add "es": spies

12. ferry
- Singular: ferry
- Rule: The "y" is preceded by a consonant ("r").
- Change "y" to "i" and add "es": ferries

13. sky
- Singular: sky
- Rule: The "y" is preceded by a vowel ("i").
- Simply add "s": skies

14. enemy
- Singular: enemy
- Rule: The "y" is preceded by a vowel ("e").
- Simply add "s": enemies

15. penny
- Singular: penny
- Rule: The "y" is preceded by a vowel ("e").
- Simply add "s": pennies

16. valley
- Singular: valley
- Rule: The "y" is preceded by a consonant ("l").
- Change "y" to "i" and add "es": valleys

17. library
- Singular: library
- Rule: The "y" is preceded by a vowel ("i").
- Simply add "s": libraries

18. supply
- Singular: supply
- Rule: The "y" is preceded by a consonant ("p").
- Change "y" to "i" and add "es": supplies

19. tray
- Singular: tray
- Rule: The "y" is preceded by a consonant ("r").
- Change "y" to "i" and add "es": trays

20. daisy
- Singular: daisy
- Rule: The "y" is preceded by a consonant ("s").
- Change "y" to "i" and add "es": daisies

21. duty
- Singular: duty
- Rule: The "y" is preceded by a vowel ("u").
- Simply add "s": duties

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#### Part 2: Writing Sentences Using Plural Forms
We will write sentences using the plural forms of the specified words.

1. ferry
- Sentence: The ferries transported passengers across the river.

2. daisy
- Sentence: The garden was filled with beautiful daisies.

3. berry
- Sentence: Children picked berries from the bushes.

4. story
- Sentence: The children listened to bedtime stories.

5. cherry
- Sentence: The pie was made with fresh cherries.

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Final Answer:

#### Plural Forms:
1. cherry → cherries
2. pony → ponies
3. story → stories
4. berry → berries
5. puppy → puppies
6. lady → ladies
7. boy → boys
8. trolley → trolleys
9. key → keys
10. monkey → monkeys
11. spy → spies
12. ferry → ferries
13. sky → skies
14. enemy → enemies
15. penny → pennies
16. valley → valleys
17. library → libraries
18. supply → supplies
19. tray → trays
20. daisy → daisies
21. duty → duties

#### Sentences:
1. ferry: The ferries transported passengers across the river.
2. daisy: The garden was filled with beautiful daisies.
3. berry: Children picked berries from the bushes.
4. story: The children listened to bedtime stories.
5. cherry: The pie was made with fresh cherries.

Final Answer Boxed:
\[
\boxed{
\text{See detailed explanations above.}
}
\]