Some men are learning martial art.
There is only one man learning martial arts.
We don't know that only one man is learning.
exists e1 s1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_learn(e1) & n_art(x2) & a_martial(s1) & Theme(s1,x2) & n_man(x1))
exists p1 x1 e1 s1 x2 x3 x4.((x1 = x2) & Theme(e1,x4) & Actor(e1,x3) & v_learn(e1) & n_art(x4) & a_martial(s1) & Theme(s1,x4) & (x2 = x3) & n_man(x2) & card_eq_1(x2) & r_only(x2))