Apostrophe s ('s) Rules with Examples

The Apostrophe s ('s) is used only to show authorship, ownership or relationship with living beings [+]. But its use is restricted to the following:

1. The names of living beings; as,
   1. The teacher's cap.
   2. The cow's tall.
2. The names of personified objects [++]; as,
   1. At death's door.
   2. Fortune's favorite.
   3. At duty's call.
   4. Sorrow's tears.
3. Nouns denoting time; as,
   1. A day's journey
   2. A week's holiday.
   3. A year's absence.
   4. Three days' grace.
   5. An hour's work
4. Nouns denoting space; as,
   1. At arm's length.
   2. A stone's throw.
   3. A hair's breadth
5. Nouns denoting weight; as,
   1. A pound's weight.
   2. A ton's weight
6. Nouns signifying certain very dignified objects; as,
   1. The sun's rays.
   2. Heaven's will.
   3. The court's decree.
   4. Duty's call.
   5. Nature's works.
7. The Apostrophe s ('s) is not to be used with lifeless things. But the following few phrases are in common use:
   1. At this finger's ends.
   2. To his heart's content.
   3. Journey's end.
   4. Out of harm's way.
   5. For mercy's sake.
   6. The ship's passengers.
   7. The boat's crew.
8. The omission of the "'s" (or the "s" after the Apostrophe).
   1. If the last syllable of a Singular Noun ends with "s"; or "ce" and the Noun is followed by "sake", the Apostrophe s('s) is omitted as,
      1. For goodness sake.
      2. For conscience sake.
   2. The "s" after the Apostrophe is omitted after all Plural Nouns ending in "s"; as,
      1. Cats' nails.
      2. Ladies' hats.
      3. Horses' tails.

Important Points about the Use of the Apostrophe s ('s)

Here are some important cautions about the use of the Apostrophe s ('s).

1. If a Plural Noun does not end in "s", the Possessive is formed by adding Apostrophe s ('s); as,
   1. Men's hats.
   2. Children's books.
2. If a Noun consist of two or more words, the Apostrophe s ('s) is attached only to the last; as,
   1. The commander-in-chief's car.
   2. The Government of Pakistan's orders.
   3. Wilson's house.
3. If two Nouns are "in Apposition" [+++], the Apostrophe s ('s) is attached to the latter; as,
   1. This is Allama Iqbal, the Poet of the East's tomb.
   2. The Khatoon-i-Pakistan, Miss Fatimah Jinnah's death was mourned by all.

[+]     If a Noun denotes a lifeless thing, it is seldom put in the Possessive Case. Thus we cannot say the book's cover or the chair's leg. Relationship with lifeless things is shown by the Preposition "of"; as,

1. The cover of this book is green.
2. Who has broken the leg of that chair?

[++]    When a Lifeless Thing of a Quality is spoken of, as if it were a Living Person, it is said to be Personified.

[+++]   When a Noun or a Noun Phrase follows another to describe it, the latter is said to be in Apposition to the former.