There are a lot of people on the roller coaster.
The roller coaster goes in a loop.
The roller could be stationary, not necessarily goes in a loop.
exists p1 x1 x4 x5.(n_coaster(x4) & of(x4,x5) & n_roller(x5) & exists x2 x3.((x1 = x2) & of(x2,x3) & on(x3,x4) & n_people(x3) & n_lot(x2)))
exists e1 x1 x2 x3.(n_coaster(x1) & of(x1,x2) & n_roller(x2) & in(e1,x3) & n_loop(x3) & Actor(e1,x1) & v_go(e1))