Four men are walking up a trail.
Four men walk up a trail while their dogs run ahead
walking up a trail implies  while their dogs run ahead
exists e1 s1 x1 x2.(a_up(s1) & Manner(e1,s1) & Theme(e1,x2) & Actor(e1,x1) & v_walk(e1) & n_trail(x2) & n_man(x1) & card_eq_4(x1))
exists e1 e2 p1 s1 x1 x2 x3 x4.(exists s2.(Theme(s2,x1) & a_ahead(s2)) & Topic(e2,p1) & Actor(e2,x1) & v_run(e2) & while(e1,x4) & n_dog(x4) & of(x4,x1) & n_thing(x1) & a_up(s1) & Manner(e1,s1) & Theme(e1,x3) & Actor(e1,x2) & v_walk(e1) & n_trail(x3) & (x1 = x2) & n_man(x1) & card_eq_4(x1))