Parts of Speech & Grammar
Middle SchoolBefore a sentence can mean anything, every word in it must belong to a category and obey the rules of that category. This chapter defines the eight parts of speech and the grammatical systems — agreement, tense, case, mood — that govern how they combine.
The eight parts of speech
English words are traditionally sorted into eight parts of speech (word-classes) according to their function in a sentence. A word's class is not fixed by the word itself but by the job it does — run is a verb in "they run" and a noun in "a morning run".
| Class | Function | Examples |
|---|---|---|
| Noun | Names a person, place, thing, or idea | teacher, London, courage, atom |
| Pronoun | Stands in for a noun | she, it, they, who, myself |
| Verb | Expresses action or a state of being | write, become, is, seemed |
| Adjective | Modifies (describes) a noun | brilliant, seven, this, tired |
| Adverb | Modifies a verb, adjective, or another adverb | quickly, very, here, however |
| Preposition | Relates a noun to the rest of the sentence | in, on, under, before, of |
| Conjunction | Joins words, phrases, or clauses | and, but, because, although |
| Interjection | Expresses emotion, standing apart grammatically | oh, alas, wow, ouch |
The grammatical systems
Word-classes carry grammatical properties that must be coordinated across the sentence:
- Number — singular vs. plural (dog / dogs). Verbs and pronouns must agree with their nouns.
- Person — first (I, we), second (you), third (he, she, they).
- Tense — the location of an event in time: past, present, future, and their perfect and progressive aspects.
- Case — the grammatical role of a pronoun: subjective (I, she, who), objective (me, her, whom), possessive (my, her, whose).
- Mood — the attitude of the verb: indicative (fact), imperative (command), subjunctive (hypothesis or wish: if I were).
The master rule that ties these together is agreement (concord): a verb agrees with its subject in number and person, and a pronoun agrees with its antecedent. "The list of items is long" — the verb agrees with the singular subject list, not the nearer plural items.
Think of the parts of speech as the roles in a play and grammar as the stage directions. Nouns and pronouns are the actors; verbs are what they do; adjectives and adverbs are the costume and the manner of performance; prepositions and conjunctions are the ropes and pulleys that connect scenes. Any word can, in principle, audition for a different role — that flexibility is what makes English so productive.
The reason agreement matters is that it removes ambiguity. When a verb signals "singular," the reader instantly knows which noun is the subject even in a long, tangled sentence. This is why "The set of tools are missing" jars: the ear expects the verb to point back to the true head noun, set. Grammar is not etiquette for its own sake; it is a redundancy system that helps meaning survive the noise of a complicated sentence.
Adjective vs. adverb. An adjective answers which? what kind? how many? about a noun ("a swift reply"). An adverb answers how? when? where? to what degree? about a verb, adjective, or adverb ("she replied swiftly"). The common error "drive slow" wants the adverb "slowly," because it modifies the verb drive.
Exercise: parse a sentence
Label the part of speech of every word in this sentence. The worked example below shows the full annotation; try it yourself first on a covered copy.
"The curious student quietly read her old book beside the window."
detThe adjcurious nounstudent advquietly verbread pronher adjold nounbook prepbeside detthe nounwindow.
Reasoning: The and the point to specific nouns (determiners/articles). Curious and old describe nouns (adjectives). Student, book, window name things (nouns). Quietly tells how she read (adverb). Read is the action (verb). Her is a possessive pronoun standing in for the student. Beside relates book to window (preposition). Note that "beside the window" is a prepositional phrase acting adverbially — it tells where.
Now you try: parse "An honest witness carefully described the strange sound." (Answer: det – adj – noun – adv – verb – det – adj – noun.)
Why is it "Each of the students has a book," not "have"?
AThe subject is each, an indefinite pronoun that is grammatically singular, so it takes the singular verb has. The phrase "of the students" is a prepositional phrase that modifies each but does not change the number of the subject. A useful test: mentally delete the prepositional phrase — "Each … has a book" — and the agreement is obvious. Other always-singular indefinites include everyone, someone, nobody, either, and neither.
When do I use who versus whom?
AWho is subjective case (it does the action); whom is objective (it receives the action or follows a preposition). Test by answering with he/him: "___ called? — He called," so use who. "To ___ did you speak? — I spoke to him," so use whom. If the answer is he/she/they, choose who; if it is him/her/them, choose whom. The final -m of whom, him, them is your mnemonic.
Is a word's part of speech ever fixed?
ARarely. Most content words can shift class by conversion (also called zero-derivation). Google was a noun that became a verb ("I googled it"); book is a noun ("a good book") and a verb ("book a table"); fast is an adjective ("a fast car"), an adverb ("run fast"), a verb ("we fast at dawn"), and a noun ("break your fast"). Because class is defined by function, always identify a word's part of speech from its job in that sentence, never from the word in isolation.
What is the subjunctive mood and is it still used?
AThe subjunctive expresses something contrary to fact, hypothetical, or demanded rather than stated as real. It survives in two main places: (1) the "were" subjunctive in unreal conditions — "If I were you" (not was), "I wish it were Friday"; and (2) the base-form subjunctive after verbs of demand or recommendation — "The board insists that he resign" (not resigns), "It is essential that she be present." It is less common in casual speech but remains a mark of careful writing.