CRT Grammar Review
Apostrophe
The apostrophe is a punctuation mark. In English it has two main functions: it marks omissions, and it assists in marking the possessives of nouns and some pronouns. Below are some examples:
Apostrophe showing possession:
- 
    Jim's hair - the hair belonging to Jim
- 
    cat's whiskers - the whiskers belonging to the cat
- 
    sister's car - car belonging to the sister
- 
    Mr. Jones's house - the house belonging to Mr. Jones
 Exceptions - Do not use the apostrophe for possessive pronouns. For example:
Correct
- 
    The group brought its van.
- 
    The book is hers.
- 
    The book is Jim's.
Incorrect
- 
    The group brought it's van.
- 
    It is his' book.
- 
    Its going to be a long day.
Apostrophe showing omission:
- 
    Can't - from cannot
- 
    I'll - from I will
- 
    It's - from it is
- 
    '70s - from 1970s
- 
    'twas - from it was
- 
    gov't - from government