A guy on a skateboard does a trick on a ramp while others watch on the other side of the ramp.
A man in a blue hat and goggles grinds his skateboard down a ramp.
All skateboarders are not wearing a blue hat and goggles. Just because he is a skateboarder doesn't imply he grinds his skateboard down a ramp.
exists e1 p1 x1 x2 x3 x4 x6.(-(x6 = x6) & n_side(x6) & exists e2 x5.(on(e2,x6) & of(x6,x4) & Actor(e2,x5) & v_watch(e2) & -(x5 = x1) & n_person(x5)) & n_ramp(x4) & n_ramp(x4) & n_person(x1) & while(e1,p1) & on(e1,x4) & Theme(e1,x3) & Actor(e1,x1) & v_do(e1) & n_trick(x3) & on(x1,x2) & n_skateboard(x2) & n_guy(x1))
exists e1 s1 x1 x2 x3 x4 x5 x6.(Theme(e1,x5) & Actor(e1,x1) & v_grind(e1) & down(x5,x6) & n_ramp(x6) & n_skateboard(x5) & of(x5,x1) & n_male(x1) & in(x1,x2) & subset_of(x4,x2) & n_goggles(x4) & subset_of(x3,x2) & n_hat(x3) & a_blue(s1) & Theme(s1,x3) & n_man(x1))