Worksheet for practicing apostrophe usage and plural forms.

Problem Explanation:

The worksheet focuses on two main tasks:
1. Proper Placement of Apostrophes: Choosing the correct contraction for phrases like "is not," "they have," etc.
2. Using Possessive Forms: Writing the correct possessive form of nouns in sentences, making them plural if necessary.

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Solution:

#### Part 1: Proper Placement of Apostrophes
For each phrase, we need to identify the correct contraction with the apostrophe.

1. "is not" = isn't
- Correct: isn't (The apostrophe replaces the missing "o" in "not.")

2. "they have" = they've
- Correct: they've (The apostrophe replaces the missing "ha" in "have.")

3. "are not" = aren't
- Correct: aren't (The apostrophe replaces the missing "a" in "not.")

4. "I am" = I'm
- Correct: I'm (The apostrophe replaces the missing "a" in "am.")

5. "she is" = she's
- Correct: she's (The apostrophe replaces the missing "i" in "is.")

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#### Part 2: Using Possessive Forms
For each sentence, we need to write the correct possessive form of the noun provided in parentheses, making it plural if necessary.

1. The ________ beak is shiny yellow and pointy. (bird)
- The bird owns the beak, so we use the singular possessive form: bird's.
- Sentence: The bird's beak is shiny yellow and pointy.

2. These ________ wheels are spinning in their cages. (hamster)
- The wheels belong to multiple hamsters, so we use the plural possessive form: hamsters'.
- Sentence: These hamsters' wheels are spinning in their cages.

3. My baby ________ doll was left outside last night. (sister)
- The doll belongs to one sister, so we use the singular possessive form: sister's.
- Sentence: My baby sister's doll was left outside last night.

4. The ________ saddles were waiting for them. (horse)
- The saddles belong to multiple horses, so we use the plural possessive form: horses'.
- Sentence: The horses' saddles were waiting for them.

5. These coins are ________ favorite collectibles. (grandpa)
- The coins are grandpa's favorites, so we use the singular possessive form: grandpa's.
- Sentence: These coins are grandpa's favorite collectibles.

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Final Answers:

#### Part 1: Proper Placement of Apostrophes
1. isn't
2. they've
3. aren't
4. I'm
5. she's

#### Part 2: Using Possessive Forms
1. bird's
2. hamsters'
3. sister's
4. horses'
5. grandpa's

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Boxed Final Answer:

\[
\boxed{
\text{1. isn't, 2. they've, 3. aren't, 4. I'm, 5. she's}
}
\]
\[
\boxed{
\text{1. bird's, 2. hamsters', 3. sister's, 4. horses', 5. grandpa's}
}
\]