Em inglês, o apóstrofo (apostrophe) usa-se:
  1   em formas possessivas:
This is John's house.
These are the boys' bicycles.

Para mais exemplos, veja possessive case
  2   em formas contraídas:
  • verbos:
    I'll see you tomorrow.
    He doesn't like coffee.

    Para mais exemplos, veja verb contractions
  • datas:
    John was born in '97.
    They met in the summer of '92.

  • horas:
    See you at 7 o'clock.
  • dialectos   (por ex. h mudo):
    When 'e arrived 'ome, 'is wife kissed 'im.
  3   em certos plurais:
  • letras:
    How many c's and m's are there in accommodation?
  • números:
    Life was hard in the 1920's.
    The way you write, your 7's look like 1's.

  • palavras:
    You have seven and's in this sentence. There are too many!
  • abreviaturas:
    John met two VIP's yesterday. (1)
    How many MP's do you know personally?
    (1) VIP = very important person
    (2) MP = Member of Parliament