Articles: a / an

Use a before a singular countable noun phrase when the following word begins with a consonant sound:

1. He wants to buy a car.
2. I need a pen to write this down.
3. She ordered a sandwich for lunch.
4. I saw a boy running in the park.
5. We need a hammer to fix the shelf.
6. I want to eat a hamburger.
7. A hungry dog will eat anything.

Use an before a singular countable noun phrase when the following word begins with a vowel sound:

1. She has an umbrella for the rainy days.
2. He is an actor in the new movie.
3. An elephant is a big animal.
4. I had an idea for the project.
5. She wore an orange dress to the party.
6. An / A herbivore is an animal that only eats plants.
7. Can you wait for me for an hour?
8. An honest person always tells the truth.

Remember that we choose a or an according to the sound of the following word, not its spelling. Some words begin with a vowel letter but have a consonant sound. In these cases, we use a rather than an:

1. A knife is a useful tool for cooking.
2. Do you live in a European country?
3. She is a university professor.
4. A unicorn is a mythical creature.