When Commas aren’t Enough

Sometimes I think we could use a punctuation mark between the comma and the semicolon. Something for when you’re using commas to separate items in a list, but you need something a little stronger to separate the whole list from other parts of the sentence. Here’s an example from Gizmag:

In the mysterious microscopic realm where the electromagnetic fields of light and matter intimately intermingle as they exchange energy, plasmons, excitons, and other particles with unexpected and usual properties abound.

You have to read that sentence twice to understand it once! The sentence is perfectly correct grammatically (if you excuse saying “microscopic” when you mean “submicroscopic”), but you can’t tell that “energy” isn’t part of the list that starts with “plasmons” until you get clear to the last word in the sentence! The sentence is correct, but it’s bad writing because it’s not clear.

Well, I’m not going to get anywhere lobbying for new punctuation. What’s the best way to fix this? Recast the sentence. Something like this:

In the mysterious microscopic realm where the electromagnetic fields of light and matter intimately intermingle as they exchange energy, particles with unexpected and unusual properties, such as plasmons, excitons, and others, abound.

We separated the list from the prepositional phrase that begins the sentence. Confusion gone.

The sentence is still rather long. How about this?

In the mysterious microscopic realm where the electromagnetic fields of light and matter intimately intermingle as they exchange energy, particles with unexpected and unusual properties abound. These include plasmons, excitons, and others.

Better.

Do you know why that comma is after the word “energy? The rule is that if a sentence starts with a prepositional phrase that has more than five words, separate the phrase from the rest of the sentence with a comma. This one has twenty words. Quite a mouthful.