The words “a/an” and “the” are called articles.  They come before nouns.  If there are any adjectives describing the noun, the articles come before the adjectives:

Pattern: indefinite article:  a/an + (adjective/s) + N
or
definite article:  the + (adjective/s) + N

The trick is knowing when to use the indefinite article a/an, and when to use the definite article the.

Use the indefinite article a/an when you are speaking about one of many:

Examples:

Pick up a loaf of bread from the bakery on your way home. (There are several loaves of bread at the bakery, but we are only getting one.)
I have a bicycle.  (There are many bikes, and I have one.)
Uncle John got a new camera for his birthday.  (There were many cameras at the store.)
Do you know if there’s a gas station nearby?  (There are many gas stations.  Is there one near here?)
Michigan is a beautiful state.  (There are fifty states, but I’m talking about one of them.)
Mr. Smith is a teacher.  (There are many teachers, and Mr. Smith is one.)

Use the definite article the when you are speaking about only one thing, a specific thing:

Examples:

The bread was freshly baked.  (= the bread from the bakery)
I had to get a new tire for the bicycle.  (= for my bicycle)
The camera has a good lens.  (= Uncle John’s new camera)
The gas station is about five blocks from here.  (= the closest one)
The state of Michigan borders three great lakes.  (= a specific state)
Mr. Smith is the math teacher.  (There is only one math teacher.)

Note:  When we introduce a thing, we use “a.”  After it’s been introduced, we use “the”:

I ordered a soup and a salad for lunch.  (introducing “soup” and “salad”)
The soup was delicious, but the salad was not fresh. (we have already been introduced to “soup” and “salad”: “soup” and “salad” are specific – the ones I ordered.)

Note:  We also use “the” when it is clear which person or thing is being referred to.

The door, the floor, the ceiling, the light, etc. (of a room)
The kitchen, the bathroom, the basement, etc. (of a house)
The bank, the post office, the library, the train station, etc. (of a city)

Examples:

Please close the door.  (= the door of the room we are in)
Mother is in the basement washing clothes. (= the basement of the house we are in)
Do you know if the library is open today?  (= the library of our town)
If you don’t behave, you’ll get sent to the principal.  (= the principal of our school)

Exercise.  Write a/an or the.

Example:

Take ______ piece of paper and write your name at ______ top.  ==> Take a piece of paper and write your name at the top.

1.    For our vacation we took ______ plane to Florida and stayed at Disneyworld.   ______ hotel was very comfortable.
2.    You ought to exercise for ______ hour every day.
3.    I picked up ______ pair of cowboy boots and three books at a garage sale.  ______ boots were like brand new, but ______ books were practically antique.
4.    Mother forgot to bring ______ can opener on our camping trip, so we had to buy ______ new one.
5.    I put ______ bandage over ______ cut on my leg.
6.    ______ children always imagine that ______ monster hides under ______ bed at night.
7.    Do you have ______ pencil I could borrow?  ______ lead in mine broke.
8.    Jack is planning to take ______ course in accounting at ______ local college in ______ spring.
9.    ______ garbage truck had ______ flat tire.
10.    ______ strong wind blew down ______ old tree down ______ street in our neighborhood.

Exercise.  Complete the sentences.  Use a or the with one of the words below.

Example:

Father and Susan are flying ______ down on the beach. (kite) ==> Father and Susan are flying a kite down on the beach.

1. Father is mowing ______.	2. Could you tell me how to get to ______?
3. Could you please close ______?	4. Teacher, I have ______.
5. Every morning I read ______ at breakfast.	6. We’d like to order ______, please.

Exercise.  Write a/an or the where necessary.

Example:

Could you please turn down radio?  ==> Could you please turn down the radio?

1.    We went to beach every day on vacation.
2.    I took train into city.
3.    Do you know how far museum is from library?
4.    New York is largest city in United States.
5.    What is largest country in world?
6.    Mother is in kitchen baking cake.
7.    I thought bed at hotel was uncomfortable.
8.    It is five-minute walk from train station to bus stop.
9.    We need to replace doorknob on front door.
10.    Do you remember name of author of that book?

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