Apostrophe uses #2 and #3

Okay, we've seen that when we want to indicate possession, the placement of the apostrophe varies. And that placement depends on whether the noun doing the possessing is singular or plural, and ends in "S" or not.

Tricky stuff, and doomed to be mis-corrected by your word processor's autocorrect. (Or word processors', if you have more than one).

So, you're warned. If you want to be absolutely sure you're not making a mistake with your possessive nouns, you have to slow down and really take a hard look at where that apostrophe is placed.

For example, the singular possessive is boy's; the plural possessive is boys'.

Now, the second use of the apostrophe is to indicate time or quantity. Very few people bother to use an apostrophe in this instance.

In a month's time, the house will be sold.
We need two weeks' notice before we can fill the order. (Notice where I placed the apostrophe in this example?)

She ate a dollar's worth of jelly beans.

And a third use for the little apostrophe is to show the omission of numbers in dates. This one should be easy to remember. When we adopt a casual tone in our writing we may say something like this: How could I forget the summer of  '69? Or was it '68?

Only five more apostrophe entries and we're done.