The stop sign is folded up against the side of the bus.
A bus hit the stop sign causing it to fold
Just because the stop sign is folded up on the side of the bus doesn't mean that the bus hit it.
exists e1 s1 x1 x2 x3 x4.(n_bus(x4) & n_side(x3) & n_sign(x1) & of(x1,x2) & n_stop(x2) & a_up(s1) & Manner(e1,s1) & against(e1,x3) & of(x3,x4) & Theme(e1,x1) & v_fold(e1))
exists e2 e1 p1 x1 x2 x3.(n_thing(x2) & n_sign(x2) & of(x2,x3) & n_stop(x3) & for(e1,e2) & Topic(e2,p1) & Recipient(e2,x2) & Actor(e2,x1) & v_cause(e2) & exists e3.(Actor(e3,x2) & v_fold(e3)) & Theme(e1,x2) & Actor(e1,x1) & v_hit(e1) & n_bus(x1))