A girl is sleeping on the grass
A girl is happily sleeping
just because the girl is sleeping in the grass doesn't mean she is happily sleeping in the grass.
exists e1 x1 x2.(n_grass(x2) & on(e1,x2) & Actor(e1,x1) & v_sleep(e1) & n_girl(x1))
exists e1 s1 x1.(a_happily(s1) & Manner(e1,s1) & Actor(e1,x1) & v_sleep(e1) & n_girl(x1))