SUBJECTS, VERBS, COMPLEMENTS, AND MODIFIERS

Sentences (all clauses, for that matter) are made up of at least two of these four basic parts: subjects, verbs, complements, and modifiers. The sentence (and the independent and dependent clause as well) must have an explicit or implicit subject and verb. In most standard written English sentences, the subject and verb are explicitly stated, and you are certainly encouraged to favor that practice in your writing for academic or career situations.

Subject
 Subjects are always nouns or noun equivalents (pronouns, gerunds, certain infinitives, phrases made from these verbals, and noun clauses). The subject is the person, place, or thing that does or controls the action of the verb. It is the concept that answers the question who? or what? does or is in relation to the verb.
 Example :

·         John eats flies. (Who eats? John does.)

·         Minerva is tired. (Who is? Minerva is.)

·         There is a book missing. (What is'? Book is. In this

Verb

Definition: Verbs are a class of words used to show the performance of an action (do, throw, run), existence (be), possession (have), or state (know, love) of a subject. To put it simply a verb shows what something or someone does.

 The verb is most often defined as the word or words that express action or state of being. The trouble with this definition is that it is so broad that it is difficult to pin down just when a word expresses action" or "being." Verbals seem to express action, and even some nouns seem to convey a sense of action (the race, his answer, my worry, for example).
Example:

• I stay with friends every year.
• I am staying with friends at the moment.

Complement

The term complement refers to the word or words of a sentence (or clause) that complete the verb or, more specifically, that complete the subject-verb relationship when such a "completing" idea is

necessary to the sense of the sentence or clause. "Ada turnips," for example is not complete. Neither is "Grows turnips," for that matter. But "Ada grows turnips" is a completed idea. Turnips completes the subject and verb, "Ada grows." (Now, "Ada grows" is a complete thought, too, but it means something entirely different from "Ada grows turnips.")

In some sentences and clauses we have an "actor" (such as Ada) and an "action" (such as grows), and that is all that is necessary to the meaning of the sentence. In other sentences and clauses there are an "actor," an "action," and something "acted upon," such as turnips in our example above.

There are several ways by which the subject and verb of a sentence or clause can be completed, depending largely on the nature of the verb. In relation to their ability to take complements in a subject-verb combination, verbs may be divided into three categories: transitive (those which require noun objects to complete them), intransitive (those which do not require noun objects), and linking (those which establish a notion of "equality" between the subject and a noun or adjective complement.

A fourth category might be added: passive. Although passive voice verbs are always formed from transitive verbs, a passive voice verb may take a complement that is either a noun or an adjective.

Let's look at these complements one by one:

1. Subjective Complement:

The subjective complement (sometimes called a predicate nominative when it is a noun or predicate adjective when it is an adjective) does just what its name implies--it completes the subject. There exists the idea of "equality" between the subject and the subjective complement established by the nature of the linking verb. (And of course that is why it is called a "linking" verb.) The verb to be in all of its forms (am, are, is, was, and were along with the various progressive and perfect tense combinations of these) is the most frequently used linking verb. In sentences or clauses using this verb, and other linking verbs, you can substitute the idea of "equals" (=) between the subject and its subjective complement.

                        Melroy is a poet.

Melroy = a poet.

2. Direct Object.-

A direct object is a noun or noun equivalent that is the receiver of the action of a subject-verb combination. It answers the question who? or what? in relation to the subject-transitive verb combination. The direct object is always in the objective case.

Pennystint hoarded trading stamps.

(Pennystint hoarded what? Trading stamps.)

3. Indirect Object.-

An indirect object is a noun or noun equivalent that, whenever it is used, always precedes a direct object and answers the question to or for whom? or what? in relation to a subject-transitive verb-direct object combination. It is always in the objective case and helps to complete verb ideas such as, give, tell, read, pay, etc., where something is done to or for someone or something else.

Pruneheart gave them trouble.

(Pruneheart gave to whom? Them; what? Trouble.)

4. Objective Complement.-

An objective complement is a noun or noun equivalent or an adjective that completes a direct object. It has the same relationship to the direct object that the subjective complement has to the subject. The idea of "to be" can always be inserted between the direct object and the objective complement. This kind of complement can occur only after the direct object and is usually found in sentences containing verbs such as, make, consider, cause, etc., where someone or something causes someone or something to be something else.

Murgatroid painted the Mercedes purple.

(Murgatoid caused the Mercedes to be purple.)

Modifier

Tells the time, place or manner of the action. Very often it's a prepositional phrase. Prepotional phrase is a group of words that begins with a preposition and ends with a noun.

Note : A modifier of time usually comes last if more than one modifier is present.
 

Example of prepositional phrases :
In the morning, at university, on the table
A modifier can also be an adverb or an adverbial phrase :
Last night, hurriedly, next year, outdoors, yesterday

Example : John bought a book at the bookstore
(modifier place)
Jill was swimming in the pool yesterday
(modifier of place)(modifier of time)

Note :
The modifier normally follows the complement, but not always. However, the modifier, especially when it's a prepositional phrase, usually can't separate the verb and the complement.

Example : She drove the car on the street
(verb) (complement)

Sumber

http://aldithogerardy.blogspot.com/2014/06/subject-verb-complement-modifier.html

http://www.zianet.com/jkline/unittwo.htm