A group of warmly dressed people in the back of a truck.
A truck is empty
There are either people in the back of the truck or it is empty.
exists e1 x1 x2 x3 x4.(n_back(x3) & a_topic(x1) & of(x1,x2) & in(x2,x3) & of(x3,x4) & n_truck(x4) & n_people(x2) & Theme(e1,x2) & v_dress(e1) & r_warmly(x2) & n_group(x1))
exists s1 x1.(Theme(s1,x1) & a_empty(s1) & n_truck(x1))