Several young people celebrate by clapping and cheering.
A group of friends celebrating at an event.
Just because people celebrate together doesn't mean that they are friends.
exists e2 e3 e1 s1 s2 x1.(by(e1,e3) & Actor(e3,x1) & v_cheer(e3) & by(e1,e2) & Actor(e2,x1) & v_clap(e2) & Actor(e1,x1) & v_celebrate(e1) & n_people(x1) & a_young(s2) & Theme(s2,x1) & a_several(s1) & Theme(s1,x1))
exists e1 x1 x2 x3 x4.(a_topic(x1) & at(e1,x4) & n_event(x4) & Actor(e1,x3) & v_celebrate(e1) & (x1 = x3) & of(x1,x2) & n_friend(x2) & n_group(x1))