A man in black surfs a big wave.
A man rides a surfboard.
To rides a surfboard is the same as surfs a wave.
exists x1.(all s1 x2.((n_wave(x2) & a_big(s1) & Theme(s1,x2)) -> exists s2 x3.(a_topic(x1) & in(x1,x3) & for(x3,x2) & n_surf(x3) & a_black(s2) & Theme(s2,x3))) & n_man(x1))
exists e1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_ride(e1) & n_surfboard(x2) & n_man(x1))