A man windsurfs in a wetsuit.
A man is windsurfing.
windsurfing is a rephrasing of windsurfs
exists x1 x2 x3.(a_topic(x1) & in(x1,x3) & n_wetsuit(x3) & n_windsurf(x1) & of(x1,x2) & n_man(x2))
exists e1 x1.(Actor(e1,x1) & v_windsurf(e1) & n_man(x1))