I just discovered something that’s contrary to what I have in my Polishing the PUGS book. ACK!
In the Usage section of my PUGS book, I point out the distinction between the two words between and among–that between is used when referring to two people or things, and among should be used for more than two.
But Merriam-Webster’s Collegiate Dictionary (the industry-standard dictionary for book publishers) says this:
There is a persistent but unfounded notion that between can be used only of two items and that among must be used for more than two. Between has been used of more than two since Old English. It is especially appropriate to denote a one-to-one relationship, regardless of the number of items. It can be used when the number is unspecified (“economic cooperation between nations”) or when more than two are unumerated (“between you and me and the lamppost”). Among is more appropriate where the emphasis is on distribution rather than individual relationships (“discontent among the peasants”).
I will definitely be making this correction in the next edition of Polishing the PUGS. If you have a copy of the 1st or 2nd edition, you might want to make a note of it.
Guess even the teacher learns something new all the time!