An apostrophe used as a contraction replaces a letter such as 'can't' the apostrophe replaces the 'o' in 'not' another common example would be 'it's' as in 'it is'. The apostrophe replaces the 'i' in 'is'.
To show possession take the noun and add an apostrophe and an 's' such as 'Mrs. Noble's friend' The apostrophe and the 's' show possession. If the noun is plural or already ends in an 's' do not put an 's' again. For example 'the birds' tree is lovely' Birds as in many birds if it was one bird it would be 'the bird's tree is lovely'
Hope this helps! good luck :)
