A sentence is made up of distinct parts or elements. The essential or PRINCIPAL ELEMENTS are the Subject and the Predicate.
The SUBJECT of a sentence is the part which mentions that about which something is said. The PREDICATE is the part which states that which is said about the subject. Ex: Man walks. In this sentence, man is the subject, and walks is the predicate.
The subject may be simple or modified: that is, may consist of the subject alone, or of the subject with its modifiers. The same is true of the predicate. Thus, in the sentence, Man walks, there is a simple subject and a simple predicate. In the sentence, The good man walks very rapidly, there is a modified subject and a modified predicate.
There may be, also, more than one subject connected with the same predicate. Ex: THE MAN AND THE WOMAN walk. This is called a COMPOUND SUBJECT. A COMPOUND PREDICATE consists of more than one predicate used with the same subject. Ex: The man BOTH WALKS AND RUNS.