A girl runs through an obstacle course outside as some boys watch.
boys watch their sister play
There is no evidence this girl is the sister of the boys. They may all just be friend.
exists e1 e2 x1 x2 x3 x4 x5 x6 x7.(Theme(e2,x7) & Actor(e2,x1) & v_watch(e2) & n_thing(x7) & through(e1,x3) & as(x5,x6) & n_boy(x6) & outside(x3,x5) & n_thing(x5) & n_course(x3) & of(x3,x4) & n_obstacle(x4) & Actor(e1,x2) & v_run(e1) & (x1 = x2) & n_girl(x1))
exists e1 x1 x2 x3.(Theme(e1,x2) & Actor(e1,x1) & v_watch(e1) & n_play(x2) & of(x2,x3) & n_sister(x3) & of(x2,x1) & n_thing(x1) & n_boy(x1))