An a unhappy couple sitting at a table in a restaurant.
a couple discuss divorce at a restaurant
Any couple could be discussing divorce, such as if their friends are getting a divorce and they are just talking through it, but their marriage is happy.  We can't tell that an unhappy couple is discussing divorce just because they are unhappy.
exists e1 s1 x1 x2 x3 x4.(a_topic(x1) & at(e1,x3) & in(x3,x4) & n_restaurant(x4) & n_table(x3) & Actor(e1,x2) & v_sit(e1) & (x1 = x2) & n_couple(x1) & a_unhappy(s1) & Theme(s1,x1))
exists e1 x1 x2 x3.(at(e1,x3) & n_restaurant(x3) & Theme(e1,x2) & Actor(e1,x1) & v_discuss(e1) & n_divorce(x2) & n_couple(x1))