A man talks on a cellphone while working.
A man talks to his wife on his cellphone.
Just because a man is talking on a cellphone does not mean he is talking to his wife.
exists s1 x1 x2 x3 x4.(a_topic(x1) & on(x1,x3) & Theme(s1,x4) & a_work(s1) & (x3 = x4) & n_cellphone(x3) & n_talk(x1) & of(x1,x2) & n_man(x2))
exists x1 x2 x3 x4.(a_topic(x1) & on(x1,x4) & n_cellphone(x4) & of(x4,x1) & n_male(x1) & n_male(x1) & to(x1,x3) & n_wife(x3) & of(x3,x1) & n_talk(x1) & of(x1,x2) & n_man(x2))