formal generalizations
1.171 Nouns referring to plants and animals can be used in the singular with the when you are making a statement about every member of a species. For example, if you say The swift has long, narrow wings, you mean that all swifts have long, narrow wings.
The primrose can grow abundantly on chalk banks.
Australia is the home of the kangaroo.
Similarly, a noun referring to a part of the human body can be used with the to refer to that part of anyone’s body.
These arteries supply the heart with blood.
…the arteries supplying the kidneys.
The is sometimes used with other nouns in the singular to make a statement about all the members of a group.
The article focuses on how to protect the therapist rather than on how to cure the patient.
These uses are fairly formal. They are not common in ordinary speech. Usually, if you want to make a statement about all the things of a particular kind, you use the plural form of a noun without a determiner. See paragraph 1.227 for more information about this.
1.172 Many common time expressions consist of just the and a noun.
We wasted a lot of money in the past.
The train leaves Cardiff at four in the afternoon.
…the changes which are taking place at the moment.
See Chapter 4 for more information about time expressions.
referring back
1.173 In each of the paragraphs above showing uses of the and a noun, it is possible to understand who or what is being referred to because the noun phrase is commonly accepted as referring to one particular person, thing, or group.
However, you can use the with any noun, if it is obvious who or what you are referring to from what has already been said or written.
The usual way of referring back to a noun is to use a pronoun, but if the second reference does not come immediately after the first one, or if it is not immediately obvious which noun is being referred to, you should use the, and the noun again. For example, if you have already mentioned that you were in a train, and then continued to tell a story, you can say afterwards The train suddenly stopped.
1.174 You can also use the and a noun when you are referring to someone or something closely connected with something you have just mentioned.
For example, you do not usually say We tried to get into the room, but the door of the room was locked. You say We tried to get into the room, but the door was locked, because it is obvious which door you are referring to.
She stopped and lit a match. The wind almost blew out the flame.
the with longer noun phrases
1.175 Although there are many situations where you use just the and a noun, there are other occasions when you need to add something else to the noun in order to make it clear which person, thing, or group you are referring to.
adding adjectives
1.176 Sometimes you can show who or what you are referring to by putting an adjective between the and the noun.
This is the main bedroom.
Somebody ought to have done it long ago, remarked the fat man.
Sometimes you need to use more than one adjective.
After the crossroads look out for the large white building.
For more information about adjectives, see paragraphs 2.2 to 2.168.
adjectives: expanding
1.177 When you use an adjective between the and a noun, you do not always do it in order to make clear who or what is being referred to.
For example, you might want to add further information about someone or something that you have already mentioned. So, if you first refer to someone as a woman in a sentence such as A woman came into the room, you might later want to refer to her as the unfortunate woman or the smiling woman.
This is a very common use in written English, especially in stories, but it is not often used in conversation.
The astonished waiter was now watching from the other end of the room.
The poor woman had witnessed terrible violence.
The loss of pressure caused the speeding car to go into a skid.
adding clauses or phrases
1.178 Another way of showing who or what you are referring to is by adding extra information after the and a noun, for example a prepositional phrase, a relative clause, a to-infinitive, an adverb of place or time, or a phrase introduced by a participle.
So you might refer to particular people at a party by using noun phrases such as the girl in the yellow dress, the woman who spilled her drink, or the man smoking a cigar.
The cars in the driveways were all Ferraris and Porsches.
The book that I recommend now costs over twenty pounds.
The thing to aim for is an office of your own.
Who made the bed in the room upstairs?
It depends on the person being interviewed.
For more information about this type of extra information that is added to a noun, see paragraphs 2.272 to 2.302.
the with uncountable nouns
1.179 You do not normally use the with uncountable nouns because they refer to something in a general way. However, the is necessary if the uncountable noun is followed by extra information such as a clause or a phrase that relates it to a particular person, thing, or group.
For example, you cannot say I am interested in education of young children. You have to say I am interested in the education of young children.
Babies need the comfort of their mother’s arms.
Even the honesty of Inspector Butler was in doubt.
I’ve no idea about the geography of Scotland.
For more information about uncountable nouns, see paragraphs 1.23 to 1.33.
superlatives
1.180 The is also used with superlative adjectives.
I’m not the best cook in the world.
They went to the most expensive restaurant in town.
See paragraphs 2.112 to 2.122 for more information about superlative adjectives.
emphasizing the
1.181 The is often used in front of a noun to indicate that someone or something is the best of its kind.