join in a group or effort, participate, take part in / increase / be added to

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 group of people, animals, etc. / (group theory) a group

group of people, animals, etc.

in a mottled or splotchy fashion, irregularly / in an energetic and swarming or flocking manner

(colloquial) to be sexually turned on, to be horny

crowded / group

everything