per

per — preposition

1. used before a unit, person, or time word to show the amount, cost, speed, or num

1.prepositionA2
Definition

used before a unit, person, or time word to show the amount, cost, speed, or number for one single case at a time.

Example

The bike shop charges NT$300 per hour for repair work.

price/rate: amount + per + time unit

Each student may borrow two library books per week this month.

number allowed per period of time

Common collocations
  • per hour
  • per day
  • per person
  • per room
  • kilometres per hour
Synonyms
  • for each

    the plain full phrase, often used when the rate needs extra emphasis

  • a

    common everyday alternative in prices and speeds, as in '$5 a kilo'

  • each

    close in meaning, but usually comes before the counted noun rather than after a number

Grammar Patterns

number/amount + per + unit

per + person/item/period of time

Usage Note

Usually follows a number or amount and comes before a singular unit noun such as 'hour', 'person', 'kilo', or 'day'. In everyday speech, 'a' can sometimes replace it in prices ('$50 a day'), but 'per' is more common in notices, reports, and formal statements.

Common Mistakes

The hotel costs NT$2,000 for night.
The hotel costs NT$2,000 per night.
use 'per' to show the price for each unit of time.
Tickets are NT$150 per adults.
Tickets are NT$150 per adult.
the noun after 'per' is normally singular.
Idioms

as per something

idiom

According to a rule, plan, or instruction that has already been set.

The team completed the project as per the client's request.

Did you follow the recipe as per the instructions?

as per normal/usual

idiom

In the same way that something normally happens or is done.

Maya arrived late for class, as per usual.

The meeting started at nine o'clock, as per normal.

per — adverb

per — abbreviation

per — prefix

Synonym discussion

Sense: preposition/1

For rates and measurements, 'per' is the most compact and neutral choice, especially in signs, reports, and formal statements: '80 kilometres per hour', 'two tickets per person'. 'For each' says the same idea more fully and is useful when you want extra emphasis or clearer rhythm in speech. 'A' is the everyday alternative in many prices and speeds: 'five dollars a kilo', 'twice a week'. 'Each' usually stands before the noun instead of after a number: 'Each guest gets one towel'. 'Apiece' works like the adverb sense of 'per' and comes after the amount: 'The oranges were ten dollars apiece.' A simple memory rule: use 'per' in compact rate expressions, but choose 'a' or 'for each' when you want a more natural spoken style.

per ↗for eachaeach ↗apiece

Common collocations

Nouns

  • per hour
  • per day
  • per person
  • per room
  • per week

Phrases

  • kilometres per hour
  • cost per night
  • price per child
  • income per person

Etymology

LatinEnglish

Borrowed from Latin 'per', a word meaning 'through', 'by means of', and also 'for each'. English kept it both as a separate word in rates and measurements, and as a prefix inside learned words such as 'permeate' and 'pervade'. The abbreviation senses were created later inside English by shortening longer words that begin with the same letters.