Subjects and Predicates

Every sentence has a subject and a predicate. The subject of a sentence is the noun, pronoun, or phrase or clause the sentence is about, and the predicate is the rest of the sentence after the subject. The predicate tells us more about what the subject does or is, and therefore must contain a verb explaining what the subject does (and can also include modifiers). The predicate is basically everything in the sentence that is not the subject.

• Einstein’s general theory of relativity has been subjected to many tests of validity over the years.
• In a secure landfill, the soil on top and the cover block storm water intrusion into the landfill.
  • This is called a compound subject, because there are two subjects in this sentence: soil and cover.
  • Notice that the introductory phrase, “In a secure landfill,” is not a part of the subject or the predicate.
• The pressure is maintained at about 2250 pounds per square inch then lowered to form steam at about 600 pounds per square inch.
  • This is called a compound predicate, because there are two predicates in this sentence: “is maintained at about 2250 pounds per square inch” and “lowered to form steam at about 600 pounds per square inch.”
• Surrounding the secure landfill on all sides are impermeable barrier walls.
  • This sentence has an inverted sentence pattern. In an inverted sentence, the predicate comes before the subject. You won’t run into this sentence structure very often, as it is pretty rare.

A predicate can include the verb, a direct object, and an indirect object.

Direct Object

A direct object—a noun, pronoun, phrase, or clause acting as a noun—takes the action of the main verb (e.g., the verb is happening to the object). A direct object can be identified by putting what?, which?, or whom? in its place.

• The housing assembly of a mechanical pencil contains the mechanical workings of the pencil.
• Lavoisier used curved glass discs fastened together at their rims, with wine filling the space between, to focus the sun’s rays to attain temperatures of 3000° F.
• The dust and smoke lofted into the air by nuclear explosions might cool the earth’s atmosphere some number of degrees.
• A 20 percent fluctuation in average global temperature could reduce biological activity, shift weather patterns, and ruin agriculture. (compound direct object)

Indirect Object

An indirect object—a noun, pronoun, phrase, or clause acting as a noun—receives the action expressed in the sentence. It can be identified by inserting to or for.

• The company is designing senior citizens a new walkway to the park area.
  • The company is not designing new models of senior citizens; they are designing a new walkway for senior citizens. Thus, senior citizens is the indirect object of this sentence.
• Please send the personnel office a resume so we can further review your candidacy.
  • You are not being asked to send the office somewhere; you’re being asked to send a resume to the office. Thus, the personnel office is the indirect object of this sentence.