Subject, Verb , Complement, Modifier

·           SUBJECT
Definition: The subject of a sentence is the noun, pronoun or noun phrase that precedes and governs the main verb. The subject is the part of the sentence that performs an action or which is associated with the action.

For example:

* He is a really nice guy.
* "He" is the subject of the sentence, controlling the verb and the complement.
* My dog attacked the burglar.
* "My dog" is the subject, controlling the verb and the rest of the sentence.
* David plays the piano
* The subject "David" performs the action of "playing the piano".
* The police interviewed all the witnesses.
* The subject the police performs the action of interviewing all the witnesses.

·           VERBS
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.

For example:

* Paul rides a bicycle.
* Here, the verb rides certainly denotes an action which Paul performs - the action of riding a bicycle.
* We buy some books to learn English verbs.
* In this example, the action word is "to buy". It tells us that the subject "we", that is the person who performs the action of the verb is "buying some books".

The verb tense shows the time of the action or state. Aspect shows whether the action or state is completed or not. Voice is used to show relationships between the action and the people affected by it. Mood shows the attitude of the speaker about the verb, whether it is a declaration or an order. Verbs can be affected by person and number to show agreement with the subject.

·           COMPLEMENT

A complement is the part of a Sentence that comes after the Verb and is needed to make the sentence complete. The following are the most important types of complement used in English:

a.  SUBJECT COMPLEMENT

Eg: He's a surveyor. (The Subject is completed by the complement to the verb. This is a Copula Verb.

b.  OBJECT COMPLEMENT

Eg: She sent him the fax. (The sentence is completed by telling us what she sent to him.)

c.   ADJECTIVAL COMPLEMENT

Eg: They'll be happy. (The sentence is completed by the Adjective; this could be extended further, they'll be happy to see us, etc..)

d.  PREPOSITIONAL COMPLEMENT

Eg: They talked about what needed doing. (The sentence is completed by the Phrase linked to the verb by the Preposition.)

·           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)

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