The people are at a party and are enjoying themselves.
Some humans enjoying themselves.
People refers to humans enjoying themselves. Hence, means the same.
exists e1 p1 x1 x2.(n_group(x2) & n_people(x1) & Theme(e1,x2) & Actor(e1,x1) & v_enjoy(e1) & exists x3.(at(x1,x3) & n_party(x3)))
exists e1 x1 x2 x3.(n_group(x3) & a_topic(x1) & Theme(e1,x3) & Actor(e1,x2) & v_enjoy(e1) & (x1 = x2) & n_human(x1))