collective noun  is a word that is used to refer to a number of people, animals, or things that we group together and speak of as a whole. Some examples: a bunch of bananasa herd of water buffaloes  (plural of  buffalo  can also be  buffalo ), a  litter of puppiesa flock of sheep , and a package of cookies

The use of a collective noun in a sentence can cause difficulty as to whether it takes a singular or plural verb. It depends on how the collective noun is to be expressed – as a group performing together or individually. If members of the group are viewed as a single unit acting together, a singular verb is used. If they are regarded as separate members acting individually, a plural verb is used.Â

A collective noun must use a correct pronoun; that is, a collective noun treated as singular must use a singular possessive pronoun. Likewise, a plural collective noun takes a plural possessive pronoun. The following table shows the examples.

Examples:

  • Our  team  has won  its  first trophy. (The singular possessive pronoun is  its , and it agrees with the  singular  collective noun  team .)
  • Our  team  are deciding on the strategy for  their  next game. (Plural possessive pronoun  their  agrees with the  plural  collective noun  team .) Â
  • The full orchestra  led by  its  new conductor is performing in the city.
  • The orchestra  do not agree to the venue for  their  next performance.
  • The audience  showed  its  approval by clapping and cheering.
  • When the curtain came down, the audience  began leaving  their  seats.

Examples:

  • The family is planning an overseas trip.

    (The family is viewed as a single group planning for an overseas trip together, so it takes a singular verb.)Â

  • The family are discussing about the plan.

    (Members of the family are looked at separately, taking part in the discussion and are not acting as a group,so a plural verb is used.)   Â

Singular and plural collective nouns
Following are examples of collective nouns being used as singular and plural nouns.  Â

Examples:

  • The explorers stumbled across  a species of plant  unknown to science.
  • Different  fish species have  been found in the coastal waters of the island. Different fish species have been found in the coastal waters of the island.
  • Data indicates  that most of the offenders come from broken home.
  • We will not draw any conclusion until we have looked at  all the data . We will not draw any conclusion until we have looked at all the data .
  • Statistics is  included in this year's Mathematics syllabus.
  • The  statistics tell  us the current trend is towards more consumers' spending.
  • The enemy is  calling for a ceasefire. 
  • The enemy were  advised to surrender. (The plural of enemy  is  enemies . But  enemy , although a singular noun, can take a plural verb such as  were  when it is regarded as a group of enemies.) Â
  • Your puppy is sleeping  underneath  my car. (Preposition)
  • His left eye was swollen with a bruise  underneath . (Adverb)
More examples
Usually, the collective noun takes a singular verb as it is looked at as a single unit. But if the emphasis is on the individual parts, the collective noun is treated as a plural and a plural verb is used.

Examples:

  • The team  is  in the bus heading for the stadium.
  • The team  are  discussing about  their  next opponent.  Â
  • The jury  has  retired to consider its verdict.
  • The jury  were  unanimous in  their  verdict.  Â
  • The public  has  the right to know how the investigation is going.
  • The public  are  calling for the bomber to be hanged or face life imprisonment. If you are uncertain about whether a singular or plural verb should be used, you can rewrite as the following. Â
  • The team members  are  discussing about  their  opponent.
  • Members of the jury/The jury members  were  unanimous in  their  verdict.
  • Members of the public  are  calling for the bomber to be hanged or face life imprisonment.  Â

Composite subject takes a singular verb

for no man. subjects can be so closely linked that they form a composite subject and expresses a single idea. A composite subject takes a singular verb.

Examples:

  • Time and tide waits  for no man. Â
  • Bread and jam is  what he eats most in the morning.
  • Bread and breakfast is  what we will look for when we arrive there.
  • Spaghetti and meatballs is  my favorite dish.

(A list of collective nouns can be found on List 3 )