person skiing off a mountain
The mountain is full of skiiers and skateboarders
The mountain is not necessarily full of skiiers and skateboarders.
exists x1 x2 x3 x4.(a_topic(x3) & Time(x3,x4) & n_skiing(x4) & n_person(x3) & off(x2,x1) & n_person(x2) & n_mountain(x1))
exists s1 x1 x2 x3 x4.(n_mountain(x1) & of(s1,x2) & subset_of(x4,x2) & n_skateboarder(x4) & subset_of(x3,x2) & n_skiier(x3) & Theme(s1,x1) & a_full(s1))