他主动帮他妈妈做家务。
他主動幫他媽媽做家務。
He takes the initiative in helping his mother do the housework.
主動
Meaning
to take the initiative
to do sth of one's own accord
spontaneous
active
opposite: passive 被動|被动[bei4 dong4]
drive (of gears and shafts etc)
Examples
他主动帮他妈妈做家务。
他主動幫他媽媽做家務。
He takes the initiative in helping his mother do the housework.