Indefinite Article with Numbers

Indefinite Article with Numbers

Rule #1.7: the indefinite article a precedes numbers with a consonant sound

They found a 2-dollar bill.

I have a 12-year old son.

Rule #1.8: the indefinite article an precedes numbers with a vowel sound

She got an 18 out of 20 on her quiz.

I saw an 80-year old man feeding pigeons.

indefinite article with numbers

[WpProQuiz 63]

The indefinite article and the number one

Rule #1.9: Do not use the indefinite article a or an with the number one

Correct: I have an essay to do.
Correct: I have one essay to do.

Incorrect: I have one an essay to do.
Incorrect: I have an one essay to do.

Use the indefinite article a or an when you mean one of something, but you are not drawing attention to the actual number. The number is not important.

Let’s go to a restaurant!
I had a strange dream last night.

Would you like a sandwich?
I have a book in my bag.

Use one when you wish to draw attention to the number,when the number is important.

My father has only one tooth.

How many spoons of sugar would you like; one or two? One spoon, please.

My doctor told me to take one pill a day.

I have only one friend.

[WpProQuiz 64]
[WpProQuiz 65]