Subject and Predicate

Every complete sentence contains two parts: a subject and a predicate. The subject is what
(or whom) the sentence is about, while the predicate tells something about the subject. In the following sentences, the predicate is enclosed in braces ({}), while the subject is highlighted.

Judy {runs}.

Judy and her dog {run on the beach every morning}.

To determine the subject of a sentence, first isolate the verb and then make a question by placing "who?" or "what?" before it -- the answer is the subject.

The audience littered the theatre floor with torn wrappings and spilled popcorn.

The verb in the above sentence is "littered." Who or what littered? The audience did. "The audience" is the subject of the sentence. The predicate (which always includes the verb) goes on to relate something about the subject: what about the audience? It "littered the theatre floor with torn wrappings and spilled popcorn."

Simple Subject and Simple Predicate

Every subject is built around one noun or pronoun (or more) that, when stripped of all the words that modify it, is known as the simple subject. Consider the following example:

A piece of pepperoni pizza would satisfy his hunger.

The subject is built around the noun "piece," with the other words of the subject -- "a" and "of pepperoni pizza" -- modifying the noun. "Piece" is the simple subject.
Likewise, a predicate has at its centre a simple predicate, which is always the verb or verbs that link up with the subject. In the example we just considered, the simple predicate is "would satisfy" -- in other words, the verb of the sentence.

A sentence may have a compound subject -- a simple subject consisting of more than one noun or pronoun -- as in these examples:

Team pennants, rock posters and family photographs covered the boy's bedroom walls.

Her uncle and she walked slowly through the Inuit art gallery and admired the powerful sculptures exhibited there.

The second sentence above features a compound predicate, a predicate that includes more than one verb pertaining to the same subject (in this case, "walked" and "admired").