The girls are playing with foam swords.
Girls are sword fighting.
They are sword fighting because they have foam swords.
exists e1 x1 x2 x3.(n_girl(x1) & with(e1,x2) & n_sword(x2) & of(x2,x3) & n_foam(x3) & Actor(e1,x1) & v_play(e1))
exists p1 x1.(exists s1 x2.((x1 = x2) & n_fighting(x2) & a_sword(s1) & Theme(s1,x2)) & n_girl(x1))