1.169 formal generalizations

Nouns referring to living things 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.
• It is irritating when breathed into the lungs.

'The' is sometimes used with other nouns in the singular to make a statement about all the members of a group.

• Too often these writings dwell 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 1.212 for more information about this.