A group of men are gathered in the forest.
Everyone is in an airplane.
a group of men can not gather in the forest and be in an airplane simultaneously.
exists e1 x1 x2 x3.(n_forest(x3) & in(e1,x3) & Theme(e1,x1) & v_gather(e1) & of(x1,x2) & n_man(x2) & n_group(x1))
all x1.(n_person(x1) -> exists p1 x2.(in(x1,x2) & n_airplane(x2)))