Crowds gather outside a 2008 summer exhibition.
A crowd starts to disperse.
Crowds usually disperse a while after they gather, so they are entirely different.
exists e1 x1 x2 x3.(outside(e1,x2) & n_exhibition(x2) & of(x2,x3) & n_summer(x3) & n_date(x2) & a_date_year_2008(x2) & a_date_year_2008(x2) & Actor(e1,x1) & v_gather(e1) & n_crowd(x1))
exists e1 p1 x1.(Topic(e1,p1) & Actor(e1,x1) & v_start(e1) & exists e2.(Actor(e2,x1) & v_disperse(e2)) & n_crowd(x1))