Q: I’m stumped by the following: “You would think a mind-warping full moon was/were beaming bright.” The word “was” sounds better to me, but “were” looks better. Which is correct?

A. “Was” is correct: “You would think a mind-warping full moon was beaming bright.”

“Would think” is the simple conditional form of the verb “think.” The auxiliary “would” is not a signal that the verb in the final clause should be in the subjunctive mood (“were” instead of “was”).

One might be tempted to use the subjunctive in a case like this because the subjunctive is the mood of the hypothetical—of speculation and possibility.

But your sentence doesn’t call for the subjunctive. We’ve written about the subjunctive several times on our blog, most recently in a posting last February.

As we say in those blog entries, the subjunctive is used today primarily for three purposes:

(1) To express a wish: “I wish a mind-warping full moon were beaming bright.”

(2) To express an “if” statement about a condition that’s contrary to fact: “If a mind-warping full moon were beaming bright, I’d howl at it.”

(3) To express that something is being asked, demanded, ordered, suggested, and so on: “A werewolf movie demands that there be a mind-warping full moon.” (The subjunctive “be” is used here instead of the indicative “is.”)

It’s worth noting, as we say in our blog entries, that the subjunctive was once much more commonly used in English than it is today.

Some archaic usages have survived, and these account for such phrases as “lest she forget” (instead of “forgets”), “God forbid” (instead of “forbids”), “come what may” (instead of “comes”), “the powers that be” (instead of “are”), “suffice it to say” (instead of “suffices”), “come spring, we’ll meet again” (instead of “comes”), and “long live the Queen” (instead of “lives”).

We’ve also noted on our blog that the subjunctive is losing ground in British English, though it’s holding its own (for now) in standard American English.

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