I saw these two headlines in a TV ad two weeks ago:

• “Police Impounded Cars”
• “Bank Foreclosed Homes”

The television commercial was intended to advertise cars and homes available at deep discounts.

In other words, the TV ad was promoting two items: (a) cars that had been impounded by police; (b) homes that had been foreclosed by banks.

But the lack of punctuation was troubling.

If the headlines were intended to be phrases, then hyphens should have been used to create modifiers of the words “Cars” and “Homes”:

• “Police-Impounded Cars”
• “Bank-Foreclosed Homes”

Unfortunately for the advertiser, the common style for punctuation of headlines is to omit periods at the ends of sentences that form headlines.

So the common expectation of viewers of the ad was that the headlines were sentences, like so:

• “Police Impounded Cars.”
• “Bank Foreclosed Homes.”

But the advertiser was promoting cars and homes, not making news announcements.

So the advertiser should have punctuated the headlines as phrases.