A woman in a white dress and colorful hat is dancing and singing on stage in front of a band.
The woman is the lead singer of the band
It can't be inferred that a band has a singer, much less a lead singer.  The woman could have spontaneously stood up to sing with the band. Karaoke Night!
exists e1 e2 s1 s2 s3 s4 x1 x2 x3 x4 x5 x6 x7 x8 x9 x10 x11 x12 x13 x14.(in(e2,x13) & of(x13,x14) & n_band(x14) & n_front(x13) & on(e2,x12) & n_stage(x12) & Actor(e2,x8) & v_sing(e2) & in(x8,x9) & n_hat(x11) & a_colorful(s4) & Theme(s4,x11) & n_dress(x10) & a_white(s3) & Theme(s3,x10) & subset_of(x11,x9) & subset_of(x10,x9) & n_woman(x8) & in(e1,x6) & of(x6,x7) & n_band(x7) & n_front(x6) & on(e1,x5) & n_stage(x5) & Actor(e1,x1) & v_dance(e1) & in(x1,x2) & n_hat(x4) & a_colorful(s2) & Theme(s2,x4) & n_dress(x3) & a_white(s1) & Theme(s1,x3) & subset_of(x4,x2) & subset_of(x3,x2) & n_woman(x1))
exists p1 s1 x1 x2 x3.(n_band(x3) & n_singer(x2) & a_lead(s1) & Theme(s1,x2) & n_woman(x1) & (x1 = x2) & of(x2,x3))