Words are classified according to their functions in sentences. It is generally agreed that there are eight parts of speech: nouns, pronouns, verbs, adjectives, adverbs, prepositions, conjunctions, and interjections.

There are also articles. The definite article is the. The specifies something or someone in particular: The person you need to see is Mr. Jones. The cat is black and white. Indefinite articles are a and an. A is used before words beginning with a consonant sound, and an is used before a vowel sound. So it’s a pear, a car, a child, but it’s an orange, an automobile, an orphan. Some vowels have a consonant sound and when they do you should use a: a union, a European. Some consonants have a vowel sound so you would use an: an hour, an honest person, an herb.

A noun is a word that denotes a thing, place, person, quality, state, or action. It functions in a sentence as the subject or object of an action expressed by a verb. It can also be the object of a preposition. There are proper nouns and common nouns. Proper nouns denote individuals and personifications and are always capitalized: Alice, Thomas, New York, The Associated Press. In the sentence, Tom is from Georgetown, back East, the words Tom, Georgetown, and East are capitalized because they refer to a specific person and specific places. A general name common to all persons, places, or things is called a common noun. In modern English, common nouns are not capitalized: girl, man, city, newspaper. For example: The boy’s home is on the east side of town.

There are concrete and abstract nouns. Anything physical that can be perceived by the senses is a concrete noun: Some books are to be tasted, others to be swallowed (Francis Bacon). An abstract noun is a quality, action, or idea which cannot be perceived by the senses: A foolish consistency is the hobgoblin of little minds (Ralph Waldo Emerson).

There are also collective nouns which name a group of individuals as though they were one: jury, committee, family, flock, regiment. And, depending on the purpose it serves, a collective noun can be either singular or plural. In the sentence, The board was unanimous in its decision, meaning it acted as one person, board is a singular form of the collective noun. In The board were arguing over increasing membership dues, the board members were acting as individuals so in this case the board is considered a plural noun.

A pronoun is an identifying word which substitutes for a noun. A pronoun can indicate a noun (such as a person’s name) already mentioned to avoid repetition: Charlie is the lead dancer; he is the tall one in the front row. There are several kinds of pronouns: personal, demonstrative, indefinite, relative, interrogative, numerical, reflective, and reciprocal.

A personal pronoun indicates (1) the speaker, (2) the person spoken to, or (3) the person, place, or thing spoken about. The speaker is first person: I, my or mine, me, we, our or ours, us. The person spoken to is second person: you, your, yours. The person, place, or thing spoken about is third person: he, she, it, they, his, her, hers, him, its, their, theirs, them. Here is a sentence that contains all three forms of personal pronouns: I loaned you my sweater but you gave it to her as a present.

Demonstrative pronouns are this, that, these, and those. They indicate a person or thing specifically: This is my sweater. That one is yours. These are my friends. Those are yours.

Indefinite pronouns refer to people or things in general. Some indefinite pronouns are: all, everybody, everything, anyone, another, many, more, several, either, neither, both, each. An example of usage in a sentence is Everybody loves somebody sometime.

A relative pronoun plays two roles, both as a pronoun and as a connective. It is a subject or object in a subordinate part of a sentence, and it joins the subordinate to a more important part of a sentence. Relative pronouns are who, which, that, what, whose, and whom. Example: He is the man whose footsteps I heard. Some compound relative pronouns are whoever, whosoever, whatever, whichever, whatsoever, and whomever.

Interrogative pronouns help ask questions. They are who, which, what, whom, and whose. Whose sweater is this? Which one of you borrowed it? Who will return it to me?

Reflective pronouns are formed by adding self or selves to the personal pronoun. They are myself, yourself, himself, herself, itself, ourselves, yourselves, and themselves. This kind of pronoun can be used as an object referring to the same person as the subject: She lives by herself.

A reciprocal pronoun represents two or more people or things interchanging the action of the verb: They love each other.

Verbs express an action, state of being, occurrence, or a relation between two things. Inflection or conjugation of a verb involves changes of form according to person and number, tense, voice (active and passive), and mood. Person and number refer to who and how many performed the action. Tense indicates the action performed. Present tense, for example, would be know; past tense would be knew; past participle would be known. I know you can dance. I knew you danced. I have known for a long time that you could dance. Voice indicates whether the subject of the verb performed (active) or received (passive) the action: Jim kicked the ball (active). The ball was kicked by Jim (passive). Mood indicates the frame of mind of the performer. Verbs have three moods: the indicative, which expresses actuality: I dance; the subjunctive, which expresses contingency: I might dance; and the imperative, which expresses command: Dance!

Adverbs modify verbs, adjectives, or other adverbs or adverbial phrases, clauses, and sentences, and alter their meaning in some way. For example, in the sentence She moves slowly, the adverb slowly modifies the verb moves. In She moves in a very slow manner, the adverb very modifies the adjective slow. In She moves very slowly, the adverb very modifies the adverb slowly. Adverbs may indicate place or direction (where, there), time (today, tomorrow), degree (nearly, completely), manner (carefully, slowly), belief or doubt (surely, maybe), and how often (never, always).

Adverbs are classified as simple or conjunctive depending on their use. A simple adverb alters the meaning of a single word. A conjunctive adverb modifies the sentence or clause it appears in.

An adjective modifies a noun or pronoun by limiting, qualifying, or describing it in one of three forms of degree: positive (happy, beautiful), comparative (happier, more beautiful), or superlative (happiest, most beautiful). Adjectives are distinguished by having endings like -er and -est, as in big, bigger, biggest. An adjective usually precedes the noun it directly modifies: blue dress, heavy book, beautiful child.

A preposition is a word that combines with a noun or pronoun to form a phrase. It expresses the relationship between words: from here to there; one after another; water under the bridge. Examples of prepositions are to, through, in, into, for, on, at, with, about, along, after, before, during, between, among, and from. In casual speech, it’s no longer a crime to end a sentence with a preposition. It’s now perfectly all right to say, That’s where she came from; He’s the man she gave her heart to; They’re the couple everybody is talking about.

Conjunctions, such as and, or, but, though, if, unless, however, and because connect sentences, clauses, phrases, or words. There are two kinds of conjunctions: coordinate and subordinate. Coordinate conjunctions join words, independent clauses, or parts of a sentence that are of the same rank or order: Virtue is bold and goodness never fearful (Shakespeare). Examples of these are and, but, or, yet; conjunctive adverbs however, nevertheless; and correlative conjunctions neither/nor. Subordinate conjunctions introduce subordinate clauses. Where, when, after, while, if, unless, since, because, although, and whether are subordinate conjunctions: I will go when I am ready. He won’t stay unless he’s invited to dinner. Subordinate conjunctions may also function as prepositions.

It is no longer considered wrong to begin a sentence with a conjunction.

Interjections are usually used to express an emotional reaction: Oh! Ow! Yipes! Hurrah! They are also used for emphasis: Aha! The interjection has no grammatical relation to the other parts of the sentence.