A rollerblader is skating against the flow of many other rollerbladers.
A rollerblader is rollerblading.
The rollerblader is skating and rollerblading no matter what the direction.
exists e1 x1 x2 x3.(n_flow(x2) & against(e1,x2) & of(x2,x3) & -(x3 = x1) & n_rollerblader(x1) & n_rollerblader(x1) & n_rollerblader(x3) & n_quantity(x3) & Actor(e1,x1) & v_skate(e1))
exists e1 x1.(Actor(e1,x1) & v_rollerblade(e1) & n_rollerblader(x1))