Children are learning about a firetruck.
The children are learning about a saftey vehicle.
A firetruck is considered a safety vehicle.
exists e1 x1 x2.(about(e1,x2) & n_firetruck(x2) & Actor(e1,x1) & v_learn(e1) & n_child(x1))
exists e1 x1 x2 x3.(n_child(x1) & about(e1,x2) & n_vehicle(x2) & of(x2,x3) & n_saftey(x3) & Actor(e1,x1) & v_learn(e1))