Street acrobats turning flips while a group of people staring with amazement on their faces.
The acrobats are doing flips while people are watching.
" Doing flips " is a rephrasing of  " turning flips ". People staring implies that they are watching.
exists e1 p1 x1.(ne_per_street(x1) & exists e3 e2 x2 x3 x4 x5 x6 x7.(while(e2,x3) & of(x3,x4) & with(e3,x6) & on(x6,x7) & n_face(x7) & of(x7,x2) & n_thing(x2) & n_amazement(x6) & Actor(e3,x5) & v_stare(e3) & (x4 = x5) & n_people(x4) & n_group(x3) & Theme(e2,x2) & Actor(e2,x1) & v_turn(e2) & n_flip(x2)) & Topic(e1,p1) & Actor(e1,x1) & v_acrobat(e1))
exists e1 p1 x1 x2.(n_acrobat(x1) & exists e2 x3.(Actor(e2,x3) & v_watch(e2) & n_people(x3)) & while(e1,p1) & Theme(e1,x2) & Actor(e1,x1) & v_do(e1) & n_flip(x2))