A boy at the end of a slip and slide.
A boy is outdoors.
You would use a slip and slid outdoors.
exists x1 x2 x3 x4 x5.(n_end(x2) & a_topic(x1) & at(x1,x2) & of(x2,x3) & n_slide(x5) & n_slip(x4) & subset_of(x5,x3) & subset_of(x4,x3) & n_boy(x1))
exists p1 x1.(exists x2.((x1 = x2) & n_outdoors(x2)) & n_boy(x1))