A tour around the city with the tour guide on the speaker.
No one can hear the tour guide because he doesn't have a megaphone or mike.
They can't hear the guide as he doesn't have a mic to project his voice over the speaker.
exists x1 x2 x3 x4.(n_speaker(x4) & n_city(x2) & a_topic(x1) & with(x1,x3) & on(x3,x4) & n_guide(x3) & of(x3,x1) & n_tour(x1) & n_tour(x1) & around(x1,x2))
exists x2 x3.(n_male(x2) & n_guide(x2) & of(x2,x3) & n_tour(x3) & -exists e1 p1 x1.(exists e2 p2.(-exists e3 x4.(Theme(e3,x4) & Actor(e3,x2) & v_have(e3) & (n_megaphone(x4) | n_mike(x4))) & because(e2,p2) & Theme(e2,x2) & Actor(e2,x1) & v_hear(e2)) & Topic(e1,p1) & Actor(e1,x1) & v_can(e1) & n_one(x1)))