A man sitting in front of a crowd of children playing the cello and a woman beside him playing a harp while the children listen.
Someone is playing music.
A man is someone and a woman is someone.  Playing the cello and playing the harp is playing music since cellos and harps are musical instruments.
exists e2 e1 p1 x1 x2 x3 x4 x5 x6 x7 x8 x9.(n_male(x8) & n_cello(x8) & a_topic(x1) & in(e1,x3) & of(x3,x4) & of(x4,x5) & Theme(e2,x7) & Actor(e2,x6) & v_play(e2) & subset_of(x9,x7) & exists e3 p2 x10.(exists e4.(Actor(e4,x5) & v_listen(e4)) & while(e3,p2) & Theme(e3,x10) & Actor(e3,x8) & v_play(e3) & n_harp(x10)) & n_child(x5) & n_child(x5) & beside(x9,p1) & n_woman(x9) & subset_of(x8,x7) & (x5 = x6) & n_crowd(x4) & n_front(x3) & Actor(e1,x2) & v_sit(e1) & (x1 = x2) & n_man(x1))
exists e1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_play(e1) & n_music(x2) & n_person(x1))