premise: A windsurfer catching air with water streaming off of the board.
hypothesis: A person is windsurfing.
explanation_1: Catching air with water streaming off of the board is windsurfing.
explanation_2: A person windsurfing  is part of the description of windsurfer catching air with water.
explanation_3: The person is windsurfing because he/she is a windsurfer.
premise_logic: exists e1 e2 x1 x2 x3 x4 x5.(n_board(x5) & a_topic(x1) & of(e2,x5) & r_off(e2) & Actor(e2,x4) & v_stream(e2) & with(e1,x4) & n_water(x4) & Theme(e1,x3) & Actor(e1,x2) & v_catch(e1) & n_air(x3) & (x1 = x2) & n_windsurfer(x1))
hypothesis_logic: exists e1 x1.(Actor(e1,x1) & v_windsurf(e1) & n_person(x1))
premise_sim: exists e1 e2 x1 x2 x3 x4 x5.(with(e1,x4) & v_stream(e2) & v_catch(e1) & r_off(e2) & of(e2,x5) & n_windsurfer(x1) & n_water(x4) & n_board(x5) & n_air(x3) & a_topic(x1) & Theme(e1,x3) & Actor(e2,x4) & Actor(e1,x2) & (x1 = x2))
hypothesis_sim: exists e1 x1.(v_windsurf(e1) & n_person(x1) & Actor(e1,x1))