active participation / being active / being energetic / being lively / being thriving / being successful / flourishing / making a big contribution / playing an active role / making a great achievement / contributing greatly / being productive

to be active (in), to participate actively (in)

main force, main body of troops / backbone, core, key figure / (baseball) center field

team

he / distal demonstrative, something far off removed from both speaker and listener: that / boyfriend

distal demonstrative, something far off removed from both speaker and listener: that, yon / particularly, male personal third person pronoun: he / by extension from he: boyfriend

he; boyfriend

a sports team which not run by the company, but by the organization of like-minded people in the local community

(baseball, softball) a center fielder

teammate