Is it the backpack of Julie or Julie’s backpack? If you ever struggled to decide whether to use ‘s (read apostrophe ess) or of to demonstrate possession in English, you’ve come to the right place. In this blog post, we go over the rules to help you decide which possessive structure in English to use according to the situation you are presented with.
Before getting into the blog post, here are some words you should know about the possessive in English so that you understand the ideas.
- Possess: to have or own
- Owner: a person or group that owns something
- Possession: something that is owned or possessed by someone
- Belong to: to be the property of (someone) : to be owned by (someone)
How to use the possessive in English
This section teaches you the six rules to properly use the possessive structure in English. Plus, you’ll learn the one mistake that many ESL students make when trying to use apostrophes.
Possessive rule #1 – is the subject animate or inanimate?
The first things you should determine are the owner and the possession of your sentence. For instance, in the sentence “This is Mark’s car”, Mark is the owner and the car is the possession. Mark is a person, so we call him an animate possessor. Animate means alive. Whenever you encounter an animate possessor, such as a person or an animal, you will use the apostrophe s (‘s). Generally, you do not use of in these sentences. Here are three examples:
- I bought Kyle’s watch yesterday. It was expensive, but I’m so glad he liked it.
Possessor: Kyle (person)
- Can we borrow your dad’s car to go to the mall?
Possessor: Dad (person)
- I love going to my boyfriend’s house.
Possessor: my boyfriend (person)
Use the apostrophe (‘s) for possession of qualities, actions, attributes
We also use the ‘s when we are talking about the qualities, actions, and attributes of an animate subject. However, it is also common to use of in such situations. Here are some examples of the possessive in English:
- Susan’s abilities are exceptional or The abilities of Susan are exceptional.
- Mr. Smith’s departure was delayed by the thunderstorm or The departure of Mr. Smith was delayed by the thunderstorm.
Even though both possessives in English work in these situations, there is a difference of emphasis between these two. In the sentences with ‘s, the possessor (Susan and Mr. Smith) is emphasized. In the sentences with of, the action/quality are emphasized.
There are situations when you have to pay attention to the sentence structure more carefully. This is a little advanced though. Basically, the meaning of a sentence can change if you are giving information about the owner instead of the possession. Take a look at the examples below. Which of the options is correct?
- The dog of the girl that I met yesterday barked all night.
- The girl’s dog that I met yesterday barked all night.
If you said (a): congratulations, you’re right! If you got this one wrong, no worries. Here’s the explanation: in option (b), we understand that you met the dog yesterday, not the girl. In option (a) it is clear that you met the girl yesterday and her dog barked all night.
Rule #2 – For possessive adjectives, never use of or ‘s
Do you remember the possessive adjectives? If not, take a look at the table below:
|Subject Pronoun||Possessive adjective||Sentence|
|I||My||My dog is big.|
|You||Your||Your brother is tall.|
|He||His||His computer is old.|
|She||Her||Her dress is so beautiful!|
|It||Its||Its toys are all destroyed.|
|We||Our||Our house is cozy.|
|You||Your||Your job is difficult.|
|They||Their||Their television is new.|
Now, let’s take a look at the possessive adjective your and the sentence “Your brother is tall”. We can’t say “The brother of you is tall”. There is no choice when using possessive adjectives. It is always possessive adjective + possession. Remember that about the possessive in English.
Possessive rule #3 – Use of when referring to a part of a whole
When talking about something animate that refers to a part of a whole we always use of. Take a look at these examples:
- A quarter of the students missed the Geometry test last Thursday.
- The rest of the class wants to retake the test.
- The majority of the students got bad grades on the test.
However, if we are talking about a part of a unit, it’s okay to use both: the ‘s and the of. Here are two examples which have the same meaning:
- The girl’s foot is broken.
- The foot of the girl is broken.
Possessive rule #4 – using ‘s with English nouns ending in s
Let’s think about nouns that end in s. Here are some of them:
When you encounter them, you have two options to make the possessive in English. You can say Lucas’ car or Lucas’s car. There is no hard rule here, so both are accepted. Some people will prefer using only the apostrophe and some would rather keep the apostrophe s. It is up to you!
Possessive rule #5 – For inanimate possessors, use of
When you have inanimate owners, such as book, plane, and project, use of to define the possession. Here are some examples of this possessive structure in English:
- The condition of the book was not acceptable.
- The departure of the plane was delayed in one hour.
- The cost of the project is higher than expected.
We also use of when referring to the part of a whole when talking about inanimate possessors. For instance:
- The top of the stairs.
- The back of the building.
However, we have two options in situations where the part is more important than the whole:
- The rooftop of the building has a pool.
The building’s rooftop has a pool.
Explanation: in this case, the part is the rooftop and the whole is the building. Since the pool is located on the rooftop, which makes it more important than the building in this particular sentence, both options are acceptable.
- The roof of the house is on fire.
The house’s roof is on fire.
Explanation: the roof is more important than the house, which is the whole, in this sentence. Therefore, both options are acceptable.
Possessive rule #6 – For complement noun groups, of is essential
Let’s keep talking about the possessive structure in English. Sometimes, you have to use of and an apostrophe does not work. Any time you describe a thought, idea, reason, criticism, belief and need, you should use of + noun. This is a complement noun group.
- I had the
- I had the idea of a picnic
politician’s criticismis fair.
- Their criticism of the politician is fair.
Further, you’ll find that some names include of.
- The law of gravity. NOT:
the gravity’s law
- The Department of Engineering. NOT:
the Engineering department
Complemental noun groups can often be rephrased as compound words, but you do not add the ‘s.
- the picnic idea
- the Linguistics Department
Don’t make this common English possessive mistake!
We don’t use ‘s to make nouns plural. This is a common error, especially with nouns made of letters. All you do is add s to the end of the noun.
- The cats are sleeping.
- They have three
- They have three TVs.
Also, be careful with it’s and its. It’s is a contraction that means “it is”. Its is a possessive adjective. Here is one example:
- I loved your car, but I am not a fan of its color (the color of the car). It’s (It is) too bright.
The word its refers to the car and has no apostrophe. If you’re unsure about the common words with contractions, you can learn more here with our punctuation guide. You can listen to a teacher explaining this difference here.
We know there are a couple of rules for you to get familiar with. Even though the possessive structure in English can seem overwhelming at first, we guarantee you that it will get better! Happy studying!