Four people are jumping from the top of a flight of stairs.
A group of boys jumps down brick stairs.
Four people does not imply a group of boys and not all stairs are brick.
exists e1 x1 x2 x3 x4.(n_top(x2) & from(e1,x2) & of(x2,x3) & of(x3,x4) & n_stair(x4) & n_flight(x3) & Actor(e1,x1) & v_jump(e1) & n_people(x1) & card_eq_4(x1))
exists e1 s1 x1 x2 x3 x4.(a_down(s1) & Manner(e1,s1) & Theme(e1,x3) & Actor(e1,x1) & v_jump(e1) & n_stair(x3) & of(x3,x4) & n_brick(x4) & of(x1,x2) & n_boy(x2) & n_group(x1))