A collective noun refers to a group of people or things, such as “family” or “flock.” It can be confusing to determine if the noun should function as singular or plural when trying to match a verb with it, so let’s break it down.

SINGULAR COLLECTIVE NOUNS:
 
Mathematics is my favorite subject.
The mob was rounding the corner.
A pair of scissors is on the kitchen counter.         

PLURAL COLLECTIVE NOUNS:
         
Where are my scissors?
The headquarters are located in Boise, Idaho.
         
EITHER WAY:

Many collective nouns can either be singular or plural, depending on their context, and here is where the confusion often lies. For example:

The jury have mixed feelings about the prosecutor’s cross-examination. (Where the individual members have differing emotions.)

The jury is sequestered. (Where the jury is a single entity.)

The staff is waiting in the conference room. (Single entity.)

The staff have special qualifications for this project. (Referring to individual members of the staff.)

My family is very dysfunctional. (Referring to the family as a unit.)

My family have always been proud of me. (Referring to the family members individually.)

Reverend Smith’s flock is very devout. (Single entity.)

Reverend Smith’s flock are always competing with each other. (Individual members are competing with each other.)

The distinctions between singular and plural usage can be pretty subtle. Your job is to decide if you want to focus on the individual or the whole, and match your verbs accordingly. As always, once you’ve made your decision, stay consistent.