Study the information about the indefinite article.
1. We use the article a/an with singular countable nouns when we talk about things in general.
A plane is more comfortable than a train.
A baker sells bread, cakes, pies.
An is used when the word starts with vowel sounds a, e, i, o, u.
an umbrella
a university
2. We can use a/an after the verbs to have and to be.
She is a photographer. She has a camera.
3. We can use both a/an and the before a singular countable noun to represent a class of people, animals, things.
A/The dolphin is more intelligent that a/the shark.
We do not use a/an with uncountable or plural nouns.
Would you like some tea?