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Apostrophes Are Used to Show Possession (one use of)
An apostrophe and the letter s are often used to show possession.
When using an apostrophe to show possession, the very first thing you have to think about is whether the possessor is singular
or plural. This is important because it determines where you must put your apostrophe. Look at these examples (the possessors
are shown in bold):

The dog's kennel.
(With one dog, the apostrophe goes before the s.)

The dogs' kennel.
(With more than one dog, the apostrophe goes after the s.)
Below are some more examples with singular and plural possessors. The reason why apostrophes for possession cause so much
trouble for writers is the number of exceptions to this basic rule. They are also covered below.
With a Singular Possessor, the Apostrophe Goes before the s
So, with one possessor, the apostrophe goes before the s.
For example:

Take the girl's hand and place it on the cushion.
(hand belonging to the girl)

I had to remove Peter's label and replace it.
(label belonging to Peter)

Wagner's music is better than it sounds.


A foolish woman knows a foolish man's faults.

A guest should be blind in another man's house.
(Mark Twain)
A friend's eye is a good mirror.
With a Plural Possessor, the Apostrophe Goes after the s
With a plural possessor, the apostrophe goes after the s.
For example:

The horses' hay is damp.
(hay belonging to the horses)
(Note: more than one horse - apostrophe after the s)

The ladies' toilets are out of bounds.
(toilets belonging to the ladies)
(Note: more than one lady - apostrophe after the s)

The fairies' wings glistened in the moonlight.
(wings belonging to the fairies)
(Note: more than one fairy - apostrophe after the s)
An Exception to the Rule (Plural Nouns Not Ending s)
Mistakes with apostrophes to show possession are very common. One reason for this is the number of exceptions to the rules
above. For example, plural words which do not end in the letter s (e.g., men, people, and children) have the apostrophe before
the s when showing possession.
Examples:

He is the people's poet.

All television is children's television.
(Richard P. Adler)

Zeus does not bring all men's plans to fulfilment.
(Homer (800 BC - 700 BC))
Leave the childrens' presents in the hall until they have gone to bed.
[correct the example]
(apostrophe should be before the s to show possession with plural words not ending in s)

My watch was stolen from the men's changing room.
Exception to the Rule (Singular Nouns Ending s)
To make things even more complicated, singular words which end in s (e.g., Charles, Wales, Paris, and Dickens) can end in '
(i.e., just an apostrophe) or 's when showing possession.
Examples:

It is Charles' birthday.
It is Charles's birthday.
(both correct)
Charles' or Charles's pal (both correct)

I have not seen Wales' new stadium.
I have not seen Wales's new stadium.
(both correct)
Les' or Les's wife (both versions correct)
Both Charles' birthday and Charles's birthday are grammatically correct. However, as a guideline, you should use the version
which best matches how you would pronounce it. In other words, use Charles's if you pronounce it "Charlesiz", but use Charles'
if you pronounce it "Charles".
More examples:

Dr Evans' report
(for those who pronounce it "Dr Evans report")

Dr Evans's report
(for those who pronounce it "Dr Evansiz report")

Miss Williams' victory
(for those who pronounce it "Miss Williams victory")

Miss Williams's victory
(for those who pronounce it "Miss Williamsiz victory")

IT Solutions' conference
(for those who pronounce it "IT Solutions conference") (where "IT Solutions" is considered as singular)

IT Solutions's conference
(for those who pronounce it "IT Solutionsiz conference")
Exception to the Rule (Compound Nouns)
Here is another quirk. Some compound nouns (e.g., sister-in-law) do not form their plurals by adding s to the end. The s is
appended to the principal word (i.e., the plural is sisters-in-law). With a noun like this, the possessive form is created by adding
's to the end, regardless of whether it is singular or plural.
Singular



sister-in-law's pond
colonel-in-chief's arrival
maid of honour's bouquet
Plural



sisters-in-law's husbands
colonels-in-chief's meeting
maids of honour's dresses
Apostrophes with Joint Ownership
Finally, joint ownership is shown by making the last word in the series possessive. Individual ownership is shown by making
both (or all) parts possessive.
Example:

Andrew and Jacob's factory
(joint ownership)
(note: only the last part is possessive)

Andrew's and Jacob's factories
(individual ownership)
(note: both parts are possessive)
(Without context, it will be assumed that Andrew has one factory and Jacob has one factory. Another construction is required
if this is not the case:
"Andrew's factories and Jacob's factories" is one option.)

India and Pakistan's problems
(common to both)

India's and Pakistan's problems
(separate problems)
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