The nominative case is used in the following constructions.
(1) The subject
(2) The predicate nominative
(3) The vocative (or nominative of direct address)
(4) The exclamatory nominative
(5) Appositive with a nominative
(6) The nominative absolute
The subject of a verb is in the nominative case.
1. Water freezes.
2. Charles climbed the mountain.
3. The boy’s face glowed with health and exercise.
4. A thousand men were killed in this battle.
In the third example, face is the simple subject. The complete subject is the boy’s face.
In the fourth, men is the simple subject. The complete subject is a thousand men.
Both face and men are in the nominative case. Face is in the singular number. Men is in the plural.
A substantive standing in the predicate, but describing or defining the subject, agrees with the subject in case and is called a predicate nominative.
A predicate nominative is also called a subject complement or an attribute.
Lobsters are crustaceans.
A good book is a faithful friend.
Shakespeare was a native of Stratford-on-Avon.
Arnold proved a traitor.
Adams was elected president.
The rule for the case of the predicate nominative is particularly important with respect to pronouns.
I am he.
It is I.
Are you she?
It was we who did it.
The predicate nominative is commonest after the copula is (in its various forms). It will be further studied in connection with intransitive verbs and passive verbs.
A substantive used for the purpose of addressing a person directly and not connected with any verb is called a vocative.
A vocative is in the nominative case and is often called a nominative by direct address or a vocative nominative.
Come, Ruth, give me your hand.
Turn to the right, madam.
Herbert, it is your turn.
Come with me, my child.
Note : A vocative word is sometimes said to be independent by direct address, because it stands by itself, unconnected with any verb. That a vocative is really in the nominative case may be seen in the use of the pronoun thou in this construction such as…..I will arrest thee, thou traitor.
A substantive used as an exclamation is called an exclamatory nominative (or nominative of exclamation).
Peace, be still.
A drum! a drum! Macbeth doth come.
Look! a balloon!
The sun! then we shall have a fine day.
Certain exclamatory nominatives are sometimes classed as interjections.
A substantive added to another substantive to explain it and signifying the same person or thing, is called an appositive and is said to be in apposition.
An appositive is in the same case as the substantive which it limits.
Hence a substantive in apposition with a nominative is in the nominative case.
Mr. Scott, the grocer, is here. [Apposition with subject.]
Tom, old fellow, I am glad to see you. [Apposition with vocative.]
The discoverer of the Pacific was Balboa, a Spaniard. [Apposition with predicate nominative.]
Note : Apposition means attachment. Appositive means attached noun or pronoun. An appositive modifies the noun with which it is in apposition much as an adjective might do (compare “Balboa, a Spaniard" with “Spanish Balboa"). Hence it is classed as an adjective modifier.