A man is at a dinner with friends.
A group of friends have gathered.
A man can be part of a group of friends, and a dinner with friends implies that a group of friends have gathered.
exists p1 x1.(exists x2 x3.(at(x1,x2) & with(x2,x3) & n_friend(x3) & n_dinner(x2)) & n_man(x1))
exists e1 x1 x2.(Actor(e1,x1) & v_gather(e1) & of(x1,x2) & n_friend(x2) & n_group(x1))