A whole bunch of people in church.
The people are at a wedding.
People can be at a church for many different occasions. Nothing about them being in a church implies that they are at a wedding.
exists s1 x1 x2 x3.(a_topic(x1) & in(x1,x3) & n_church(x3) & of(x1,x2) & n_people(x2) & n_bunch(x1) & a_whole(s1) & Theme(s1,x1))
exists p1 x1.(n_people(x1) & exists x2.(at(x1,x2) & n_wedding(x2)))