one

Meanings

1. 1pronounsingularformal

   used in formal English to mean any person, including the speaker

   Grammar: Refers to people in general; it takes a singular verb and its possessive form is one's: One should do one's best.

   Patterns

   • one should do something
   • one never knows
   • one's own

   One should always check one's work before handing it in.

   One never knows what the future will bring.

   In this job, one has to be patient with customers.

2. 2number

   the number 1; a single person or thing

   Grammar: Used for counting and before nouns: one book, one of them.

   Patterns

   • one of something
   • one or two

   I only need one more stamp to finish the set.

   One of my friends is moving to Canada.

   There's only one seat left.

3. 3determinerbefore a noun

   used to talk about a particular but not specified day, time, or thing

   Grammar: Often used with days and times: one day, one morning.

   Patterns

   • one day
   • one morning
   • one time

   One day I'll travel around the world.

   One evening, we heard a strange noise outside.

   I met her one summer at a language school.

Common combinations

one another

The two brothers always help one another.

one by one

The students came in one by one.

one and only

This is your one and only chance to apply.

one or two

I have one or two questions about the plan.

Synonyms and how they differ

you

You is the normal informal way to mean people in general; one sounds formal or old-fashioned.

single

Single emphasizes 'only one' and is used before a noun; one is the plain number.

Word family

oneself pronoun

Refers back to one as the object: It's important to look after oneself.

once adverb

Means one time: I've only been there once.

first adjective

Comes before all others in order: She was the first to arrive.

Commonly confused: one or won?

Practice

Make it your own

Write a sentence using “one”, then check it and compare it with the examples above.

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