Spelling, grammar and punctuation matter. Let's go over a few things.

First, apostrophes, which are particularly, especially near and dear to my heart, and so horrifically abused. Yes, I'm talking to you, and you know who you are. Dude, you're killing me.

First, apostrophes have NOTHING to do with plurality. Nothing. The plural of 'cat' is 'cats'. Let's use 'cats' in a sentence:

The insane woman who lives across the road has seventy cats inside her house.

NOT:

The insane woman who lives across the road has seventy cat's inside her house. WRONG! BAD! KILLING ME!!

If you put apostrophes into plural words, people will think that you are stupid, even if you aren't. It is that simple.

Second, apostrophes are used to show POSSESSION.

If the cat possesses something, then it is "the cat's". For example:

The dog's favorite treat is eating the cat's puke.

The PUKE belongs to the cat, so it is the CAT'S puke. As an added bonus in this sentence, the FAVORITE TREAT is the possession of the dog, so it is the DOG'S favorite treat. Possession, possession, possession.

Now, if the dog in question lived in the crazy woman's house with seventy cats and the the dog ate the puke from many or all of the seventy cats, that sentence would be:

The dog's favorite treat is eating the cats' puke.

When you have a plural word that is also possessive, the apostrophe goes on the outside of the 's'.

Completing the progression, if the crazy woman had multiple puke-eating dogs instead of just one, that sentence would be:

The dogs' favorite treat is eating the cats' puke.

Thirdly, apostrophes are used to indicate a CONTRACTION. 'Do not' becomes 'don't'. We put the apostrophe between the 'n' and the 't' because we have removed the 'o' in 'not'. The apostrophe goes in the place of the missing letter or letters.

Are not becomes aren't.
I have becomes I've.
She had and she would become She'd
Contraction, contraction, contraction.

Fourthly, the words 'it's' and 'its' must have their respective rules memorized. It is quite easy to distinguish between the two if you simply remember this mnemonic device:

IT can never possess anything.

Now certainly the word 'it' is used in the possessive case, but the point of this little mnemonic device is to remind us that the possessive 'its' never, ever has an apostrophe. Once I learned this little rule as a kid, the whole 'its-it's' question was put to bed forever.

The cat is quite chagrined when the dog eats its puke. No apostrophe, because this is a possessive 'its'.

When 'it's' is a contraction for 'it is', then you use the apostrophe to replace the missing 'i' from the word 'is'.

It's pretty gross to sit around and watch a bunch of dogs eat cat puke.

Given these rules for 'its' and 'it's', it follows that there is NO SUCH WORD as its' with an external apostrophe. I would insert an example here about dogs and cats and vomit consumption, but there is no example because there is no such word as its'.

That is all.

3. Your vs. you're.

Your is the possessive of you.

You're is the contraction of you are.

Your punctuation is awful, and it's killing me, but you're a'ight.

The punctuation YOU POSSESS (your) is awful, and IT IS (contracted to it's) killing me, but YOU ARE (contracted to you're) alright (redneck contracted to a'ight).

That is all.

4. There-Their-They're

There: a place. Over there. Interchangeable with 'yonder'.

Their: plural possessive. It's their house. Their body odor is intolerable.

They're: contraction of they are.

They're going to eat their lunch over there.

That is all.


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