Of these, the Noun is the most important, as all the others are more or less dependent upon it. A Noun signifies the name of any person, place or thing, in fact, anything of which we can have either thought or idea.
Nouns are varied by Person, Number, Gender, and Case. Person is that relation existing between the speaker, those addressed and the subject under consideration, whether by discourse or correspondence. The Persons are First, Second and Third and they represent respectively the speaker, the person addressed and the person or thing mentioned or under consideration.
Number is the distinction of one from more than one. There are two numbers, singular and plural; the singular denotes one, the plural two or more. The plural is generally formed from the singular by the addition of s or es.
Gender has the same relation to nouns that sex has to individuals, but while there are only two sexes, there are four genders, viz., masculine, feminine, neuter and common. The masculine gender denotes all those of the male kind, the feminine gender all those of the female kind, the neuter gender denotes inanimate things or whatever is without life, and common gender is applied to animate beings, the sex of which for the time being is indeterminable, such as fish, mouse, bird, etc. Sometimes things which are without life as we conceive it and which, properly speaking, belong to the neuter gender, are, by a figure of speech called Personification, changed into either the masculine or feminine gender, as, for instance, we say of the sun, He is rising; of the moon, She is setting.
Case is the relation one noun bears to another or to a verb or to a preposition. There are three cases, the Nominative, the Possessive and the Objective. The nominative is the subject of which we are speaking or the agent which directs the action of the verb; the possessive case denotes possession, while the objective indicates the person or thing which is affected by the action of the verb.
An Article is a word placed before a noun to show whether the latter is used in a particular or general sense. There are but two articles, a or an and the.
An Adjective is a word which qualifies a noun, that is, which shows some distinguishing mark or characteristic belonging to the noun.
DEFINITIONS
A Pronoun is a word used for or instead of a noun to keep us from repeating the same noun too often. Pronouns, like nouns, have case, number, gender and person. There are three kinds of pronouns, personal, relative and adjective.
A verb is a word which signifies action or the doing of something. A verb is inflected by tense and mood and by number and person, though the latter two belong strictly to the subject of the verb.
An adverb is a word which modifies a verb, an adjective and sometimes another adverb.
A preposition serves to connect words and to show the relation between the objects which the words express.
A conjunction is a word which joins words, phrases, clauses and sentences together.
An interjection is a word which expresses surprise or some sudden emotion of the mind.
Adapted from: http://www.lousywriter.com/introduction_english_grammar.php
