A man on a bike that is doing a trick.
a man doing a trick in front of others
Doing a trick does not imply it is in front of others.
exists e1 x1 x2 x3 x4.(a_topic(x1) & on(x1,x2) & Theme(e1,x4) & Actor(e1,x3) & v_do(e1) & n_trick(x4) & (x2 = x3) & n_bike(x2) & n_man(x1))
exists e1 x1 x2 x3 x4 x5.(a_topic(x1) & Theme(e1,x3) & Actor(e1,x2) & v_do(e1) & in(x3,x4) & of(x4,x5) & -(x5 = x1) & n_person(x1) & n_person(x5) & n_front(x4) & n_trick(x3) & (x1 = x2) & n_man(x1))