Grammar: a/an/the

We often need to use a, an  or the when we talk about nouns.

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We use a with consonant sounds. For example, computer, pen, teacher, banana
We use an with vowel sounds. For example, orange, apple, umbrella.


You need to think about the sound not the spelling. We say an umbrella, but we say a university, because university begins with a consonant sound.  We say a hotel, but we say an hour, because hour begins with a silent h.

a/an means one/ singular so we cannot use a/an with uncountable nouns. We cannot say a milk, a sugar. We cannot use a/an with plural nouns, so we cannot say a people, a men, an apples.

We always use a/an with job titles. For example: I'm a teacher, he's a student, she's a doctor.

Try these exercises to practise:
1. https://elt.oup.com/student/result/engelem/a_grammar/unit02/2c_1?cc=global&selLanguage=en 
2. https://elt.oup.com/student/result/engelem/a_grammar/unit02/2c_2?cc=global&selLanguage=en&mode=hub 
3. https://elt.oup.com/student/headway/elementary4/grammar/unit04/hwy_elem_unit04_3?cc=global&selLanguage=en&mode=hub 


We use the when we know the thing we are talking about. Often this is because there is only one: the sky, the sun, the moon, the capital city, the world

We use a/an the first time we talk about something. We use the the second time we talk about something. For example:  
I'm eating a sandwich. The sandwich is delicious.
She's reading a book. The book is really boring.

Try these exercises to practise:
1. https://elt.oup.com/student/result/engelem/a_grammar/unit03/3b_1?cc=global&selLanguage=en
2. https://elt.oup.com/student/result/engelem/a_grammar/unit03/3b_2?cc=global&selLanguage=en