English has four major word classes: nouns, verbs, adjectives and adverbs. They have many thousands of members, and new nouns, verbs, adjectives and adverbs are often created. Nouns are the most common type of word, followed by verbs. Adjectives are less common and adverbs are even less common.
Many words belong to more than one word class. For example, book can be used as a noun or as a verb; fast can be used as an adjective or an adverb:
It’s an interesting book. (noun)
We ought to book a holiday soon. (verb)
He loves fast cars. (adjective)
Don’t drive so fast! (adverb)
A suffix can often, but not always, tell us if a word is a noun, verb, adjective or adverb:
nouns | verbs | adjectives | adverbs |
station government cruelty | soften identify industrialise | drinkable Japanese useless | carefully easily sadly |
A good learner’s dictionary will tell you what class or classes a word belongs to.
The other word classes include prepositions, pronouns, determiners, conjunctions and interjections.
Prepositions describe the relationship between words from the major word classes. They include words such as at, in, on, across, behind, for:
We went to the top of the mountain. (to describes the relationship between went and top; of describes the relationship between top and mountain)
Are you ready for lunch yet? (for describes the relationship between ready and lunch)
Pronouns are words which substitute for noun phrases, so that we do not need to say the whole noun phrase or repeat it unnecessarily. Pronouns include words such as you, it, we, mine, ours, theirs, someone, anyone, one, this, those:
That’s Gerry in the photo. He lives in Barcelona.
This jacket’s mine. That must be Linda’s.
Determiners come before nouns. They show what type of reference the noun is making. They include words such as a/an, the, my, his, some, this, both:
Have you got a ruler I can borrow?
I need some paper for my printer.
This phone isn’t easy to use.
Conjunctions show a link between one word, phrase or clause and another word, phrase or clause. They include and, but, when, if, because:
Joe and Dan are brothers.
It was okay, but I wouldn’t recommend it as a restaurant.
We’ll ring you when we get to London.
Interjections are mostly exclamation words (e.g. gosh! wow! oh!), which show people’s reactions to events and situations:
A:I’m giving up my job.
B:Oh.
Yippee! I don’t have to go to work tomorrow!
Gosh! What an awful smell!
The different word classes can form the basis of phrases. When they do this, they operate as the head of the phrase. So, a noun operates as the head of a noun phrase, a verb as the head of a verb phrase, and so on. Heads of phrases (H) can have words before them (e.g. determiners (det), adjectives (adj), adverbs (adv)) or after them (e.g. postmodifiers (pm) or complements (c)):
Noun phrase (underlined)
[DET]That [ADJ] [H]old box [PM (clause)]you left in the kitchen has got a hole in it.
Adverb phrase (underlined)
It all happened [ADJ]very [H]suddenly.
Prepositional phrase (underlined)
[H]The President [C]of the United States arrives tomorrow.
