A pack of wolves run through the woods [duplicate]

Solution 1:

This is a matter of formal agreement versus notional agreement.

Formal agreement is the strictly grammatical agreement between the verb and the subject: a singular subject must be matched by a singular verb.

Notional agreement is more flexible, and allows the verb to matched to the idea - notion- of the subject. For example

"The board of directors is in agreement"

versus

"The board of directors are arguing"

In the first, the notion is unity so a singular verb is appropriate, in the second the notion is disunity so a plural verb is used.

This works when the individuals and the collective are the same thing. 'The Board' and 'the directors' have the same referent. They are the same idea- the same thing. In your example 'the pack' and 'the wolves' are the same thing. This contrasts with, say, 'the bag of footballs' in which the 'the bag' and 'the footballs' are entirely different things.

As a native BE speaker, I would say that notional agreement is more usual in BE. Sometimes we treat groups as singular and sometimes as plural. Text books often say that formal agreement is more usual in AE, but I am not entirely convinced.

Getting around to your wolf pack, I would say:

"A pack of wolves runs through the woods."

because they run in unison. If they stopped to eat I would change:

"A pack of wolves eat [or "are eating"] in the woods"

because eating is an individual activity.

If somebody else said "A pack of wolves run through the woods" I wouldn't say it was wrong. It is just different.

Solution 2:

Is only one sentence correct? Are both sentences acceptable?
It depends. It depends on the idea, concept or image you want to express.

A pack of wolves run through the woods

The verb, run, agrees with the plural noun, wolves. In other words, all the wolves (none excluded), run through the woods. The implication being that there are many wolves in this group.

A pack of wolves runs through the woods.

The verb, runs, agrees with the singular noun, pack. In this case, we look at the group of wolves as being a single unit. The pack is composed of individual wolves but because they each share common characteristics, we see them acting as a whole. As if they were an army of soldiers, which brings me neatly to:

"an army of soldiers is" has 421 results in Google books.

An army of soldiers is a powerfully organized, ferocious and destructive animal _{The Spirit of the Age, Volumes 1-2 By William Henry Channing}

Whereas "army of soldiers are" has 1,800 results

An army of soldiers are turned loose in the blood stream that can kill anything that attacks it from cancer to the common cold _{A Cure to Die For by Stephen G. Mitchell}

In the first example we see the soldiers as a single entity, powerful and unified. In the second we see each individual soldier as a potential threat to our health and well being.