1. The article AN is used before singular, countable nouns which begin with vowel sounds
2. Examples: He is an actor. She didn't get an invitation. I saw an eagle at the zoo.
3. Remember that A(AN) means "one" or "a single". You cannot use A(AN) with plural nouns. Examples: I saw a bears in Yellowstone National Park. Not Correct I saw bears in Yellowstone National Park. Correct
4. The article "A" is used before singular, countable nouns which begin with consonant sounds.
5. Examples: He is a teacher. She doesn't own a car. I saw a bear at the zoo.
6. Examples: He is an actor. She didn't get an invitation. I saw an eagle at the zoo.
7. If there is an adjective or an adverb-adjective combination before the noun, A(AN) should agree with the first sound in the adjective or the adverb-adjective combination. Examples: He is an excellent teacher. I saw a really beautiful eagle at the zoo
