1. example: an umbrella a uniform an uncle a university
2. The words "a" and "an" are items to indicate a thing
3. "An" is used when the word starts with a vowel sound.
3.1. example: an apple, an orange, an eraser
3.2. The boy always eats an apple in the mornings. You need an umbrella because it’s raining a lot. An ant was walking on my pillow.
4. Exceptions The letter U is part of the vowels, but in some words it may sound like a consonant. Specifically it takes the sound of the pronoun of the second singular person "you", so the sound is related to the consonant letter 'y', considering the sound of the 'u' as a consonant sound in these cases.
5. Exceptions There are words that start with a consonant but the first SOUND of the word is a vocal sound. an hour (The "h" in this word is not pronounced.)
5.1. example: a horse, a house
5.2. There are also words that start with a vowel, but the first SOUND of the word is a consonant sound.
6. "A" when the word that follows is a consonant (letters of the alphabet without counting those of the vowels).
6.1. example: a book, a dog, a ball, a pencil
6.2. prayers: They have a car. The dog is playing with a ball. I am reading a book.
