English grammar worksheet focusing on the articles "a" and "an" with images and words for children to practice.

The task in the image is to fill in the blanks with either "a" or "an" before each noun. The choice between "a" and "an" depends on whether the word following it begins with a consonant sound or a vowel sound:

- Use "a" before words that start with a consonant sound.
- Use "an" before words that start with a vowel sound.

Let's solve the problem step by step:

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List of Words and Solutions:

1. orange → an orange (starts with a vowel sound)
2. apple → an apple (starts with a vowel sound)
3. umbrella → an umbrella (starts with a vowel sound)
4. rabbit → a rabbit (starts with a consonant sound)
5. bus → a bus (starts with a consonant sound)
6. university → a university (starts with a consonant sound)
7. desk → a desk (starts with a consonant sound)
8. elephant → an elephant (starts with a vowel sound)
9. sheep → a sheep (starts with a consonant sound)
10. lemon → a lemon (starts with a consonant sound)
11. egg → an egg (starts with a vowel sound)
12. uniform → a uniform (starts with a consonant sound)
13. igloo → an igloo (starts with a vowel sound)
14. giraffe → a giraffe (starts with a consonant sound)
15. banana → a banana (starts with a consonant sound)
16. uncle → an uncle (starts with a vowel sound)
17. flower → a flower (starts with a consonant sound)
18. ear → an ear (starts with a vowel sound)
19. bear → a bear (starts with a consonant sound)
20. ring → a ring (starts with a consonant sound)
21. arm → an arm (starts with a vowel sound)
22. farmer → a farmer (starts with a consonant sound)
23. eye → an eye (starts with a vowel sound)
24. eraser → an eraser (starts with a vowel sound)

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Final Answer:

1. an orange
2. an apple
3. an umbrella
4. a rabbit
5. a bus
6. a university
7. a desk
8. an elephant
9. a sheep
10. a lemon
11. an egg
12. a uniform
13. an igloo
14. a giraffe
15. a banana
16. an uncle
17. a flower
18. an ear
19. a bear
20. a ring
21. an arm
22. a farmer
23. an eye
24. an eraser

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Explanation:

- The key is to focus on the sound of the first letter, not just the letter itself. For example:
- "university" starts with a "y" sound, which is a consonant sound, so we use "a".
- "ear" starts with an "e" sound, which is a vowel sound, so we use "an".

This rule ensures consistency in English grammar when using indefinite articles.

Final Answer Boxed:
\[
\boxed{
\text{1. an orange, 2. an apple, 3. an umbrella, 4. a rabbit, 5. a bus, 6. a university, 7. a desk, 8. an elephant, 9. a sheep, 10. a lemon, 11. an egg, 12. a uniform, 13. an igloo, 14. a giraffe, 15. a banana, 16. an uncle, 17. a flower, 18. an ear, 19. a bear, 20. a ring, 21. an arm, 22. a farmer, 23. an eye, 24. an eraser}
}
\]