Fun with grammar
cadhla just posted a neat new song here, that woke my inner grammarian. Who got inspired. Here's the result:

While apostrophes are useful things when forming a possessive
The tendency of English to confuse things is impressive
(You'll have noticed, if you're neither unobservant nor myopic
That they also form contractions, but that's quite another topic)
If the objects that you're speaking of belong to Bill and Sue
Then "Bill's" would be a proper form, and "Sue's" is valid too
The rule in play is different, though, if your need is to render
A sentence where the owner of the object has no gender
For the lesson is that less is more, and more is surely less
When you place a stray apostrophe between "i t" and "s"
And though trying to remember this odd rule may give you fits
When the neutral pronoun owns a thing, it isn't "it's", it's "its"