Grammar Pulis

You asked:

Which is correct?
A block of rooms has been reserved.
A block of rooms have been reserved.

Grammar Pulis answers:

Yippee! A subject verb agreement question.

I'll answer your question by first, giving the right answer, and then explaining why.

The grammatically correct sentence is:

A block of rooms has been reserved.


Why? The verb has to agree with the headword or the main noun. In this case the headword is block. "of rooms" are modifiers. Because the headword (block) is in singular form, the verb (has) needs to be in singular form as well.


Here are more examples that follow this rule. I have used bold font for the headwords.

The stack of records has been moved into another cabinet.
A series of concerts has been scheduled for summer.
A herd of zebras passing by is making me dizzy.
A cast of thousands gets ready for the first shooting day.
My set of silver and onyx jewelry is missing.

At your service,
Grammar Pulis

Source: Understanding Grammar, Third Edition by Martha Kolln