Grammar worksheet teaching the use of "a" and "an" with vowel sounds, featuring a fun monster illustration.

Problem Explanation:

The worksheet focuses on the correct usage of a and an as indefinite articles. The rule is:
- Use a before words that begin with a consonant sound.
- Use an before words that begin with a vowel sound.

#### Key Points to Remember:
1. The decision is based on the sound of the first letter, not just its appearance.
2. Some letters (like "h") can be tricky; if they are silent, the next letter's sound determines whether to use a or an.

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Solution:

#### Part 1: Write *a* or *an* in front of each word.

1. boot: Consonant sound → a
- Sentence: a boot

2. egg: Vowel sound → an
- Sentence: an egg

3. fox: Consonant sound → a
- Sentence: a fox

4. peg: Consonant sound → a
- Sentence: a peg

5. artist: Consonant sound → a
- Sentence: a artist (Note: Although "artist" starts with a vowel, the pronunciation begins with a consonant sound.)

6. ear: Vowel sound → an
- Sentence: an ear

7. arm: Vowel sound → an
- Sentence: an arm

8. ice block: Consonant sound → a
- Sentence: a ice block

9. nose: Consonant sound → a
- Sentence: a nose

10. drum: Consonant sound → a
- Sentence: a drum

11. orange: Vowel sound → an
- Sentence: an orange

12. ox: Consonant sound → a
- Sentence: a ox

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#### Part 2: Write *a* or *an* in each space.

1. I saw ______ old car.
- "Old" begins with a consonant sound → a
- Sentence: I saw a old car.

2. I have ______ black dog.
- "Black" begins with a consonant sound → a
- Sentence: I have a black dog.

3. I climbed ______ oak tree.
- "Oak" begins with a consonant sound → a
- Sentence: I climbed a oak tree.

4. Sally ate ______ ice cream.
- "Ice" begins with a consonant sound → a
- Sentence: Sally ate a ice cream.

5. The spider ate ______ ant.
- "Ant" begins with a vowel sound → an
- Sentence: The spider ate an ant.

6. Mike saw ______ big fire.
- "Big" begins with a consonant sound → a
- Sentence: Mike saw a big fire.

7. The story came to ______ end.
- "End" begins with a vowel sound → an
- Sentence: The story came to an end.

8. What ______ ugly monster!
- "Ugly" begins with a vowel sound → an
- Sentence: What an ugly monster!

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Final Answers:

#### Part 1:
1. a boot
2. an egg
3. a fox
4. a peg
5. a artist
6. an ear
7. an arm
8. a ice block
9. a nose
10. a drum
11. an orange
12. a ox

#### Part 2:
1. a
2. a
3. a
4. a
5. an
6. a
7. an
8. an

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Boxed Final Answer:

\[
\boxed{
\text{Part 1: a, an, a, a, a, an, an, a, a, a, an, a}
}
\]
\[
\boxed{
\text{Part 2: a, a, a, a, an, a, an, an}
}
\]