A football player running with the ball is being tackled by his opponent.
A quarterback running with the ball is being tackled by his opponent.
football player is not necessarily a quarterback
exists e2 e1 x1 x2 x3 x4 x5.(n_opponent(x5) & of(x5,x4) & n_male(x4) & n_ball(x4) & Actor(e2,x5) & Theme(e2,x1) & v_tackle(e2) & with(e1,x4) & Actor(e1,x3) & v_run(e1) & (x1 = x3) & n_player(x1) & of(x1,x2) & n_football(x2))
exists e1 x1 x2 x3 x4.(n_opponent(x4) & of(x4,x3) & n_male(x3) & n_ball(x3) & Actor(e1,x4) & Theme(e1,x1) & v_tackle(e1) & with(x1,x3) & n_run(x1) & of(x1,x2) & n_quarterback(x2))