A young man is' heading' a ball while on the beach, another young man, in the background, looks at him.
Nobody is on the beach
If the nobody is on the beach, the man is not on the beach.
exists p1 s1 s2 x1 x7 x8.(n_beach(x8) & n_background(x7) & exists x2 x3.((x1 = x2) & all x4.(n_ball(x4) -> exists e1 p2 x5.(exists e2 s3 x6.(on(e2,x8) & at(e2,x1) & Actor(e2,x6) & v_look(e2) & in(x6,x7) & n_man(x6) & a_young(s3) & Theme(s3,x6) & -(x6 = x1)) & while(e1,p2) & Theme(e1,x5) & Actor(e1,x3) & v_head(e1) & for(x5,x4) & n_'(x5))) & (x2 = x3) & n_'(x2)) & n_male(x1) & n_man(x1) & n_man(x1) & a_young(s2) & Theme(s2,x1) & a_young(s1) & Theme(s1,x1))
exists x2.(n_beach(x2) & -exists p1 x1.(on(x1,x2) & n_person(x1)))