A ballerina in a black dress and tights dances in front of a concrete wall.
a human practices ballet
The ballerina is practicing dancing. It's reasonable to assume she is dancing ballet.
exists s1 s2 x1 x2 x3 x4 x5 x6 x7.(a_topic(x1) & in(x1,x2) & subset_of(x4,x2) & in(x4,x6) & of(x6,x7) & n_wall(x7) & a_concrete(s2) & Theme(s2,x7) & n_front(x6) & n_dance(x4) & of(x4,x5) & n_tights(x5) & subset_of(x3,x2) & n_dress(x3) & a_black(s1) & Theme(s1,x3) & n_ballerina(x1))
exists s1 x1 x2.(a_topic(x1) & Time(x1,x2) & n_ballet(x2) & n_practice(x1) & a_human(s1) & Theme(s1,x1))