A man is pulled behind a boat on a knee board while another doing the same begins to fall.
There are two males on knee boards being pulled behind a boat, one is an expert and the other is a novice.
Just because there are two men knee boarding does not necessarily mean that one is an expert and the other is a novice.
exists e1 p1 x1 x2 x3 x4 x7.(n_same(x7) & exists e3 e2 p2 x5 x6.(Topic(e3,p2) & Actor(e3,x5) & v_begin(e3) & exists e4.(Actor(e4,x5) & v_fall(e4)) & Theme(e2,x7) & Actor(e2,x6) & v_do(e2) & (x5 = x6) & n_thing(x5)) & while(e1,p1) & behind(e1,x2) & on(x2,x3) & n_board(x3) & of(x3,x4) & n_knee(x4) & n_boat(x2) & Theme(e1,x1) & v_pull(e1) & n_man(x1))
exists p1 p2 p3 x1 x2 x3.(n_other(x3) & exists x10.((x3 = x10) & n_novice(x10)) & exists x9.((x2 = x9) & n_expert(x9)) & n_thing(x2) & card_eq_1(x2) & exists e1 x4 x5 x6 x7 x8.((x1 = x4) & behind(e1,x8) & n_boat(x8) & Theme(e1,x7) & v_pull(e1) & (x4 = x7) & on(x4,x5) & n_board(x5) & of(x5,x6) & n_knee(x6) & n_male(x4) & card_eq_2(x4)))