Boys look over a bridge on to a lake.
A group of boys are getting ready to fish off a bridge.
The boys may already be involved in a activity and not getting ready to do something.  The boys may not plan to fish.  The planned activity may be somewhere other than off the bridge.
exists e1 x1 x2 x3.(over(e1,x3) & n_bridge(x3) & r_on(e1) & to(e1,x2) & n_lake(x2) & Actor(e1,x1) & v_look(e1) & n_boy(x1))
exists e1 p1 x1 x2.(exists p2 s1.(Topic(s1,p2) & Actor(s1,x1) & a_ready(s1) & exists e2 s2 x3.(a_off(s2) & Manner(e2,s2) & Theme(e2,x3) & Actor(e2,x1) & v_fish(e2) & n_bridge(x3))) & Topic(e1,p1) & Actor(e1,x1) & v_get(e1) & of(x1,x2) & n_boy(x2) & n_group(x1))