had been grouping

• past perfect progressive

  past perfect progressive

  Used to describe an action that was ongoing continuously in the past up until another past event interrupted it.

  of group.
  group

  noun

  any collection or assemblage of persons or things; cluster; aggregation.

Related Words

• association
• band
• body
• class
• club
• company
• crowd
• faction
• gang
• organization
• party
• society
• troop