Boys and men, mostly all wearing helmets, hang on to two separate cars while they ride skateboards.
A gang of skateboarders is trying to escape from foot police.
Just because the boys and men are hanging on two separate cars while they ride skateboards does not indicate  they are escape the foot police.
exists e1 p1 s1 s2 x1 x2 x3 x4 x5 x6 x7.(rel(e1,x5) & subset_of(x7,x5) & n_man(x7) & subset_of(x6,x5) & n_boy(x6) & exists e2 x8.(Theme(e2,x8) & Actor(e2,x1) & v_ride(e2) & n_skateboard(x8)) & n_thing(x1) & while(e1,p1) & Theme(e1,x2) & Actor(e1,x1) & v_wear(e1) & rel(x2,x3) & on(x3,x4) & n_car(x4) & a_separate(s2) & Theme(s2,x4) & card_eq_2(x4) & r_to(x4) & n_hang(x3) & n_helmet(x2) & n_all(x1) & a_mostly(s1) & Theme(s1,x1))
exists e1 p1 x1 x2.(Topic(e1,p1) & Actor(e1,x1) & v_try(e1) & exists e2 x3 x4.(from(e2,x3) & n_police(x3) & of(x3,x4) & n_foot(x4) & Actor(e2,x1) & v_escape(e2)) & of(x1,x2) & n_skateboarder(x2) & n_gang(x1))