A crowd of people in a parade.
A group of people are at an event.
A crowd of people is a group of people.   A parade is an event.
exists x1 x2 x3.(a_topic(x1) & in(x1,x3) & n_parade(x3) & of(x1,x2) & n_people(x2) & n_crowd(x1))
exists p1 x1 x2.(exists x3.(at(x1,x3) & n_event(x3)) & of(x1,x2) & n_people(x2) & n_group(x1))