One man plays an acoustic guitar, while another accompanies him on the accordion.
Two men are seasoned performers.
Just because they play instruments does not mean they are seasoned performers.
exists e1 p1 s1 x1 x2 x4.(n_accordion(x4) & exists e2 x3.(on(e2,x4) & Theme(e2,x2) & Actor(e2,x3) & v_accompany(e2) & n_thing(x3)) & n_male(x2) & while(e1,p1) & Theme(e1,x2) & Actor(e1,x1) & v_play(e1) & n_guitar(x2) & a_acoustic(s1) & Theme(s1,x2) & n_man(x1) & card_eq_1(x1))
exists p1 x1.(exists s1 x2.((x1 = x2) & n_performer(x2) & a_seasoned(s1) & Theme(s1,x2)) & n_man(x1) & card_eq_2(x1))