the, a/an

Using a/an and the in English

In English, we use a/an and the with singular countable nouns (a car, an apple, the book, etc.). They help the listener know whether we are talking about something in general or something specific.

1. a and an: first time / any one

We use a or an when:

• We mention something for the first time.
• We mean any one of many possible things or people.

Use a before consonant sounds, and an before vowel sounds.

• a dog, a house, a university (you-ni-)
• an apple, an orange, an hour (no “h” sound)

Examples:

• I bought a book yesterday. (The listener doesn’t know which book. It’s the first time you mention it.)
• Can you recommend a restaurant? (Any restaurant is OK, not a specific one.)
• She is a doctor. (We talk about her job: one doctor among many.)
• He wants to buy a car. (Any car; we don’t know which one yet.)

2. a/an for type or kind

We also use a/an to say what type of thing or person something is.

Examples:

• We stayed in a cheap hotel. (We describe the type of hotel: “cheap”.)
• I need a dentist. (Any dentist, not a specific one.)
• She is a good teacher. (Her type or quality as a teacher is “good”.)
• They live in a small apartment. (Type of apartment: “small”.)

3. the: specific and known

We use the when it is clear which specific person or thing we mean. This can be because:

• We mentioned it before.
• The situation or context makes it obvious.

3.1. After we mention something for the first time

First time: use a/an. Second time: use the.

• I saw a movie last night. The movie was really scary. (First: a movie – we don’t know which one. Second: the movie – now we know which one.)
• She bought a dress. The dress is blue.

3.2. When the context makes it clear

Sometimes we use the even the first time we mention something, because both the speaker and the listener know which one.

• Can you turn off the light? (We are in a room. It’s clear which light.)
• I have to talk to the manager. (In a store, office, or hotel, there is usually only one manager.)
• We need to go to the station. (In this town, it’s clear which station we mean.)
• Close the door, please. (There is a specific door in this situation.)

4. Common expressions with the

We use the with some common places in town when we think of them as services or specific buildings.

• go to the bank
• go to the post office
• go to the supermarket
• go to the airport

Examples:

• I have to go to the bank this afternoon. (A specific bank that both speakers understand.)
• She’s at the post office right now.

5. Fixed expressions with a: frequency

We use a in fixed expressions to talk about how often something happens.

Structure:

number + times + a + period of time

Examples:

• once a week (one time every week)
• twice a month (two times every month)
• three times a day (three times every day)

In sentences:

• I go to the gym three times a week.
• She calls her parents once a day.

6. Fixed expressions with a: price and measurement

We also use a with price, weight, distance, etc. It means “for each”.

Structure:

price/amount + a + unit

Examples:

• £1.50 a kilo (one pound fifty for each kilo)
• $2 a liter (two dollars for each liter)
• 60 miles an hour (60 miles for each hour)
• $500 a week (500 dollars for each week)

In sentences:

• The apples are £1.50 a kilo.
• He earns $15 an hour.

7. Quick summary

• a/an = first mention, any one, or type/kind of thing.
• the = specific, known, or obvious from the context.
• Use a in fixed expressions: once a week, three times a day, $2 a liter, £1.50 a kilo.

When you are not sure, ask yourself: “Is this any one of many (use a/an) or a specific one that we both know (use the)?”