When writing, we use an apostrophe and an “s” (like this: 's) to show that something belongs to or is closely associated with a person.
Example
- This is Peter’s father. ✅
 - This is the father of Peter. ❌
 - My cat‘s ears are white. ✅
 - The ears of my cat are white. ❌
 
However, for inanimate objects (not people or pets), use of instead of 's.
Example
- The end of the street ✅
 - The street‘s end ❌
 - A picture of the eclipse ✅
 - The eclipse‘s picture ❌
 
Exceptions
We can use 's with time expressions.
Example
- yesterday’s party, today’s news, last year’s conference
 - two hours’ walk, three days’ drive, one month’s salary,
 
When we talk about places or organizations, we can use both of and 's.
Example
- The decision of the country
 - The country’s decision
 - The prediction of the bank
 - The bank’s prediction
 - He’s one of Britain’s best chefs.
 
If there is a determiner (a, some, this, etc.) before the nouns, then we should use of instead of 's.
Example
- Some friends of Anna’s came to the party. ✅
 - Anna’s some friends came to the party. ❌
 - Some friends of hers came to the party. ✅
 - Isn’t that a friend of your sister’s? ✅
 
In cases where the person is described with a lengthy phrase, we typically use of instead of the 's to maintain sentence clarity and flow.
Example
- This is the child of the neighbors who live next door. ✅
 - This is
 the neighbors who live next door’schild. ❌- That’s the wife of one of my friends from Liverpool. ✅
 - That’s
 one of my friends from Liverpool’swife. ❌
References