People engage in a tandem skydive on a cloudy day.
Ten people are forming a circle while skydiving.
People doesn't imply ten people.
exists e1 s1 x1 x2 x3 x4.(on(e1,x4) & n_day(x4) & a_cloudy(s1) & Theme(s1,x4) & in(e1,x2) & n_skydive(x2) & of(x2,x3) & n_tandem(x3) & Actor(e1,x1) & v_engage(e1) & n_people(x1))
exists e2 e1 x1 x2.(while(e1,e2) & Actor(e2,x1) & v_skydive(e2) & Theme(e1,x2) & Actor(e1,x1) & v_form(e1) & n_circle(x2) & n_people(x1) & card_eq_10(x1))