The boy is going to dive in the river.
A boy is going to dive head first into a river.
dive doesn't always mean  head first
exists e1 x1 x2 x3.(n_river(x3) & n_boy(x1) & in(e1,x3) & to(e1,x2) & n_dive(x2) & Actor(e1,x1) & v_go(e1))
exists e1 s1 x1 x2 x3 x4.(into(e1,x4) & n_river(x4) & a_first(s1) & Manner(e1,s1) & to(e1,x2) & n_head(x2) & of(x2,x3) & n_dive(x3) & Actor(e1,x1) & v_go(e1) & n_boy(x1))