The predicate of a sentence is a verb or verb phrase which says something about the subject.
In order to get a correct definition of the subject, let us examine two specimen sentences:—
1. But now all is to be changed.
2. A rare old plant is the ivy green.
In the first sentence we find the subject by placing the word what before the predicate,—What is to be changed? Answer, all. Consequently, we say all is the subject of the sentence.
But if we try this with the second sentence, we have some trouble,—What is the ivy green? Answer, a rare old plant. But we cannot help seeing that an assertion is made, not of a rare old plant, but about the ivy green; and the real subject is the latter. Sentences are frequently in this inverted order, especially in poetry; and our definition must be the following, to suit all cases:—
Subject.
The subject is that which answers the question who or what placed before the predicate, and which at the same time names that of which the predicate says something.
The subject in interrogative and imperative simple sentences.
341. In the interrogative sentence, the subject is frequently after the verb. Either the verb is the first word of the sentence, or an interrogative pronoun, adjective, or adverb that asks about the subject. In analyzing such sentences, always reduce them to the order of a statement. Thus,—