be on the ball(v = verb.cognition) be with it, know the score, know what's going on, know what's what - be well-informed;
is one way to know
Sample sentences: Somebody ----s

ball, ball and chain, ball bearing, ball boy, ball carrier, ball cartridge, ball club, ball cock, ball fern, ball field, ball game, ball gown, ball hawk, ball hawking, ball nettle, ball nightshade, ball of fire, ball over, ball the jack, ball up, ball valve, beach ball, billiard ball, bocce ball, bocci ball, boccie ball, bosie ball, bowling ball, breaking ball, camphor ball, cannon ball, change-of-pace ball, codfish ball, cotton ball, cricket ball, croquet ball, crystal ball, cue ball, curve ball, dirt ball, eight ball, fair ball, fancy-dress ball, feather ball, field hockey ball, fish ball, fly ball, foul ball, golf ball, ground ball, gum ball, gutter ball, hair ball, have a ball, jump ball, lacrosse ball, lucille ball, masked ball, masquerade ball, matzah ball, matzo ball, matzoh ball, medicine ball, melon ball, minie ball, musket ball, net ball, ninepin ball, no ball, object ball, on the ball, passed ball, ping-pong ball, play ball, playground ball, polo ball, pool ball, popcorn ball, porcupine ball, punching ball, rifle ball, roulette ball, rugby ball, skittle ball, smoke ball, soccer ball, spit ball, squash ball, submarine ball, tea ball, tennis ball, volley ball, whitworth ball, wiffle ball