A family prepares to ride on the water.
The family has never done this before.
Prepares to ride on the water does not imply having never done it before.
exists e1 p1 x1 x2.(n_water(x2) & Topic(e1,p1) & Actor(e1,x1) & v_prepare(e1) & exists e2.(on(e2,x2) & Actor(e2,x1) & v_ride(e2)) & n_family(x1))
exists e1 s1 s2 x1 x2.(n_thing(x2) & n_family(x1) & a_never(s2) & Manner(e1,s2) & a_before(s1) & Manner(e1,s1) & Theme(e1,x2) & Actor(e1,x1) & v_do(e1))