Theory:

 
 
Collective Noun
Meaning
Swarm
A group of insects.
Shoal
A group of fish.
Group
A very general term used to describe people, things, and animals.
Crowd
To describe a group of people.
Gang
To describe a group of criminals; also used to describe a group of workers, sailors or dock workers.
Mob
To describe an angry or unruly group of people; used to describe a group of kangaroos.
Staff
A group of people who work in the same place.
Crew
To denote a group of workers; also used to describe aircraft and ships personnel.
Choir
A large, organized group of singers.
Orchestra
A large, organized group of instrumentalists, led by a conductor.
Panel
A group of experts.
Board
A group of people, usually professionals, who take on an advisory role.
Troupe
A group of actors or acrobats; also used to describe a group of monkeys.
Bunch
To describe objects such as grapes, flowers, keys, or bananas.
Pile
An untidy collection of items like rubbish.
Heap
A mounded collection of items.
Set
A group of matched objects such as dishes; also used to describe rules or a social group of people.
Stack
A group of items neatly laid one on top of another; i.e., a stack of egg crates.
Series
Used to discuss serials, books, or events that follow one after another, eg: Harry Potter.
Shower
To describe rain, although it can be used to describe gifts or compliments.
Fall
Often used to discuss weather, such as rain, snow or hail.
Flock
A group of birds; also used to discuss  hooved animals such as sheep or goats.
Pack
A group of canine animals such as wolves; also used to describe playing cards and packages containing multiple objects.
 
Important!
Click here for the list of a collective noun.