People are river rafting.
People are rafting
River rafting is a type of rafting activity.
exists e1 x1 x2.(Time(e1,x2) & n_river(x2) & Actor(e1,x1) & v_raft(e1) & n_people(x1))
exists e1 x1.(Actor(e1,x1) & v_raft(e1) & n_people(x1))