Two individuals on a beach jumping up with their arms and legs spread wide open.
Two boys are riding bikes on the beach.
It's implied that the two individuals are the two boys. They can't be riding bikes because they're jumping with their arms and legs spread wide open.
exists e1 e2 s1 s2 x1 x2 x3 x4 x5 x6 x7.(Theme(e2,x7) & Actor(e2,x1) & v_spread(e2) & n_open(x7) & a_wide(s2) & Theme(s2,x7) & on(x1,x2) & with(e1,x4) & n_leg(x6) & n_arm(x5) & subset_of(x6,x4) & subset_of(x5,x4) & of(x4,x1) & n_thing(x1) & a_up(s1) & Manner(e1,s1) & Actor(e1,x3) & v_jump(e1) & (x2 = x3) & n_beach(x2) & n_individual(x1) & card_eq_2(x1))
exists e1 x1 x2 x3.(n_beach(x3) & on(e1,x3) & Theme(e1,x2) & Actor(e1,x1) & v_ride(e1) & n_bike(x2) & n_boy(x1) & card_eq_2(x1))