Someone is surfing underneath a wave on a white surfboard.
The person is female.
Someone does not imply female.
exists e1 s1 x1 x2 x3.(underneath(e1,x2) & on(x2,x3) & n_surfboard(x3) & a_white(s1) & Theme(s1,x3) & n_wave(x2) & Actor(e1,x1) & v_surf(e1) & n_person(x1))
exists s1 x1.(n_person(x1) & Theme(s1,x1) & a_female(s1))