Two people biking beside a railroad.
A man and woman are biking by a railroad
People does not imply a man and a woman necessarily.
exists e1 x1 x2 x3.(a_topic(x1) & beside(e1,x3) & n_railroad(x3) & Actor(e1,x2) & v_bike(e1) & (x1 = x2) & n_people(x1) & card_eq_2(x1))
exists e1 x1 x2 x3 x4.(by(e1,x4) & n_railroad(x4) & Actor(e1,x1) & v_bike(e1) & n_woman(x3) & n_man(x2) & subset_of(x3,x1) & subset_of(x2,x1))