a or an - the difference - exercise

Indefinite articles

Use a / an to say what a person or thing is.

Examples: He is a friend.

a - indefinite article

a : one person or one thing

Indefinite article before consonant: a.

Example: a friend, a box

an - indefinite article

an: before a, e, i, o, u

Examples: an apple,  an animal

But:
an hour (h is not pronounced)
a university,  a user, a unit ...

Definite article the

Use the to refer to people or objects that are unique and to refer to something that has already been mentioned. Use the when you know, which thing or person you mean.

English a an - definite and indefinite articles exercises

a an - definite and indefinite articles with free online exercises, examples and sentences, questions and a an - definite and indefinite articles negative sentences.

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