Two black-haired boys are squatting on the ground while holding handfuls of marbles.
Two black-haired boys squatting on the ground holding handfuls of marbles.
Are squatting on the ground is a rephrasing of squatting on the ground.
exists e2 e1 s1 x1 x2 x3 x4.(n_ground(x2) & while(e1,e2) & Theme(e2,x3) & Actor(e2,x1) & v_hold(e2) & of(x3,x4) & n_marble(x4) & n_handful(x3) & on(e1,x2) & Actor(e1,x1) & v_squat(e1) & n_boy(x1) & a_black-haired(s1) & Theme(s1,x1) & card_eq_2(x1))
exists e2 e1 s1 x1 x2 x3 x4 x5 x6.(n_ground(x3) & a_topic(x1) & on(e1,x3) & Theme(e2,x5) & Actor(e2,x4) & v_hold(e2) & of(x5,x6) & n_marble(x6) & n_handful(x5) & (x3 = x4) & Actor(e1,x2) & v_squat(e1) & (x1 = x2) & n_boy(x1) & a_black-haired(s1) & Theme(s1,x1) & card_eq_2(x1))