"a number of"

[sarathy.srinivas]

Hi,

I am confused as to whether i should treat "a number of" as a plural or singular subject. For example, consider the following sentences:

There are a number of people in the stadium
There are a number of reasons for me to get an MBA

Can i replace the verb "are" with "is"? I'm a bit confused with the grammar rules here, so I would appreciate it if anyone could shed some light on this.

Thank you.

[dmitryknowsbest]

In this usage, "a number of" is being used idiomatically to mean "many," so the plural verb should be used.

The example we use in the class slides is:

The number of dogs IS large.
A number of dogs ARE here.

In the first case, the subject is "number." It's the number that is large; the dogs may be quite small. :)

In the second case, we are using "a number of" to mean "many" again. The subject is "dogs," hence the plural noun.

We would only use "is" in your examples if we changed the subject of the sentence:

"The number of people in the stadium is decreasing rapidly now that it's raining."