A group of people rowing a boat.
A group of people are trying to find a waterfall to fall off of.
One cannot be rowing and trying to find a waterfall simultaneously.
exists e1 x1 x2 x3 x4.(a_topic(x1) & of(x1,x2) & Theme(e1,x4) & Actor(e1,x3) & v_row(e1) & n_boat(x4) & (x2 = x3) & n_people(x2) & n_group(x1))
exists e1 p1 x1 x2.(Topic(e1,p1) & Actor(e1,x1) & v_try(e1) & exists e2 p2 x3.(Theme(e2,x3) & Actor(e2,x1) & v_find(e2) & Topic(x3,p2) & exists e3 x4.(r_off(e3) & of(e3,x4) & n_thing(x4) & Actor(e3,x3) & v_fall(e3)) & n_waterfall(x3)) & of(x1,x2) & n_people(x2) & n_group(x1))