People sit on the curb watching an event.
An event is happening with people watching.
people watching implies watching an event
exists e2 e1 x1 x2 x3.(n_curb(x2) & for(e1,e2) & Theme(e2,x3) & Actor(e2,x1) & v_watch(e2) & n_event(x3) & on(e1,x2) & Actor(e1,x1) & v_sit(e1) & n_people(x1))
exists e1 e2 x1 x2 x3.(with(e1,x2) & Actor(e2,x3) & v_watch(e2) & (x2 = x3) & n_people(x2) & Actor(e1,x1) & v_happen(e1) & n_event(x1))