A group of people have gathered to watch some girls sing.
There are girls performing alone.
A group gathered around, you cannot be performing alone.
exists e1 p1 x1 x2.(Topic(e1,p1) & Actor(e1,x1) & v_gather(e1) & exists e3 e2 x3 x4.(Theme(e3,x3) & Actor(e3,x1) & v_watch(e3) & Actor(e2,x4) & v_sing(e2) & (x3 = x4) & n_girl(x3)) & of(x1,x2) & n_people(x2) & n_group(x1))
exists p1 x1 e1 s1 x2 x3.((x1 = x2) & a_alone(s1) & Manner(e1,s1) & Actor(e1,x3) & v_perform(e1) & (x2 = x3) & n_girl(x2))