Two guys in front of microphones.
The people are professional singers.
Phones does not imply professional singers
exists x1 x2 x3.(a_topic(x1) & in(x1,x2) & of(x2,x3) & n_microphone(x3) & n_front(x2) & n_guy(x1) & card_eq_2(x1))
exists p1 x1.(n_people(x1) & exists s1 x2.((x1 = x2) & n_singer(x2) & a_professional(s1) & Theme(s1,x2)))