Essential Concepts and Terms for Grammar Study


A verb is a word to convey an action (e.g. run, read, bring), or a state of being (e.g. is, has, live). We will call them action verbs and non-action verbs respectively.

It is an essential element in a sentence.


A noun is a word to represent an object (e.g. book), a concept (e.g. chemistry) and so forth. A pronoun is a word designated to substitute a noun (e.g. this, he, them). A proper noun is a noun representing a unique entity (e.g. London, John).

Pronouns are relatively few. The rest of the nouns belong to an open category, with new words emerged and added to the dictionary in a living language.


An adjective (e.g. big) is a word designated to modify a noun (e.g. house).

Notice that many nouns (including pronouns) can be used to modify other nouns (e.g. chocolate factory, our country). Some modified forms of verbs can also be used to modify nouns too (e.g. smiling girl, broken heart).


An adverb is a word used to modify adjectives, verbs, another adverbs, and even a whole sentence, but never used to modify nouns.

In English, an adverb often ends in -ly (e.g. happily). Other common example adverbs are: very, more, indeed.


A particle is a word used to indicate relationships between the word it tries to link (its object), and the rest of the sentence.

In English, it is usually called preposition (e.g. in, at, for), because it is used before its object. In Japanese or Korean, it is also called postposition or marker.

Modifying a Word: Conjugation and Declension

Conjugation is modifying a verb from its dictionary or principle form. Declension is the modification for nouns and adjectives.

In English, for example, goes is a modified form of the verb go, and men is a modified form of the noun man.


A phrase is part of a sentence which by itself is meaningful.

The most common types of phrases are noun phrases and verb phrases, which function like nouns and verbs respectively in a sentence.

Subject and Predicate

A complete sentence usually contains a subject and a predicate. A subject is a noun or noun phrase in a sentence, it is what the sentence is about. A predicate describes the subject in a sentence.

Running is a good exercise.
Running is the subject, and is a good exercise is the predicate.

Object and Transitive/Intransitive Verbs

An object which complements an action verb completes the verb’s meaning. It is always part of a predicate.

A direct object answers the question “what?” in a sentence, and an indirect object is usually the recipient of the direct object.

I give you a book.
book is the direct object and you is the indirect object

Not all action verbs take objects. Verbs that take objects are called transitive verbs, those do not take objects are called intransitive verbs. A verb can be both transitive and intransitive in different situations.

She breaks the vase.
break is a transitive verb
He jumps.
jump is an intransitive verb
I eat (apples).
eat is both transitive and intransitive

Related Grammar Points