Grammar Drill here.

Hi, I'm Minion Foggedy and this week I have a quick and dirty tip about AND OR.

That's AND slash OR.

And it tidbit with some useful and funny made-up words.

First, Kelly asked whether AND OR in a subject makes the verb singular or plural.

For example, what verb should she use in a sentence like this?

This message AND OR attachments.

Is confidential?

Or this message AND OR attachments ARE confidential.

You'd be hard-pressed to find a style guide that doesn't admonish you to drop the AND

OR and rewrite the sentence with just AND or just OR.

If you feel you MUST use AND OR, my non-scientific survey of professional writing shows that

you probably want to treat AND OR as though it makes the subject plural.

For example, Kelly's sentence would read, this message AND OR attachments ARE confidential.

Usually, rewriting the sentence with OR better reflects the meaning you're trying to accomplish

with AND OR.

But sometimes people try to add clarity by adding OR both to the end of the sentence.

As in, this message or attachments OR both are confidential.

In Kelly's case, a slight rewrite using the word AND is probably the better choice.

This message AND any attached files are confidential.

And that was your quick-interity tip, whenever possible, avoid AND OR, but if you MUST use

it in the subject of a sentence, treat the subject as plural.

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