An article by Fred McArdle, West Brunswick.
Q: We have arguments about it’s and its at our place, and it’s causing chaos. Could you please give us an explanation we can understand, so we can eat our tea in peace?
A: It is a common problem, and one that can even lead to hostility. I’ll do my best to sort it out briefly for you.
The quick answer to your question is that it’s means specifically either it is or it has, and is in either case a contraction, or shortening of two words into one.
The word its (without apostrophe) means belonging to it , and is called a possessive adjective. It is a legitimate single word, and is not a contraction at all.
The easy way I remember this is to “tie” the word its to the word his ( as in his hat), but I don’t know if that works for anyone but me! For example, in a sentence like The car has lost its wheels, if I can replace the word its with the word his and still feel that the sentence is grammatically OK , then its has no apostrophe. The sentence The car has lost his wheels sounds OK grammatically, so its has no apostrophe in the original sentence.
Anyway, the correct usage of the two words can be represented by these three sentences:
I think it’s going to rain soon ( meaning it is)
Aha! I think it’s already started! (meaning it has)
This poor little dog has lost its way.
By way of general explanation, there are 2 common reasons to use apostrophes.
The first is for contractions such as that’s for that is (as in That’s my dog) or even for that has (as in That’s been fixed already).
The simple way to regard this apostrophe is as a space-filler, to stand in for the missing letters. Thus, do not becomes don’t, should not becomes shouldn’t, cannot becomes can’t, etc.
The other use of the apostrophe is to show possession, whether something is literally owned by someone or just “belongs” to it in a looser sense. So, we get sentences like
John’s book is green.
The boy’s bag has been squashed by a truck
The elephant’s tail is ridiculously short.
The book’s ending left me asking questions.
The complications that upset many people come with singular and plural nouns, as in phrases like
the horses’ (or horse’s?) hay, or the men’s (or mens’ ?) coats….
The rule that I always use is as follows: work out what the “basic” word is (and it is normally a noun), then add an apostrophe plus the letter “s”. If, however, it already ends in “s”, then just add an apostrophe. In most cases, this gets around the problem of having to work out what’s plural and what’s singular.
For example, if I want to write The peoples seats on the tram, I find the basic word people, add an apostrophe and “s”, and I get The people’s seats…
If I want to write The foxes holes were flooded (i.e., several foxes), I find the basic noun foxes, add only an apostrophe because there is already an “s” on the end of the word, and I get foxes’ holes.
So here are some correct versions for you to chat about:
This situation’s going to be the death of me ( meaning situation is…..)
Where’s my $x~*# shoe? (meaning Where is…)
I think Tom’s lost his marbles (meaning Tom has…)
I found the mouse’s nest inside the piano ( this means specifically that the nest belongs to one mouse)
Where is the mice’s nest? (This sentence sounds funny to me, although it is correct grammatically, as the nest is said to belong to all the mice, which it probably does in a mouse democracy. Probably, to avoid an awkward sound, I would write or say Where is the mouse nest? or Where have the mice got their nest? with perhaps the odd expletive thrown in.)