The worker in the fluorescent vest is taking a break and sitting down.
The group plays pool
You cannot be sitting down and playing pool because it requires you to stand up to play the game.
exists e1 e2 s1 s2 s3 x1 x2 x3 x4 x5.(n_vest(x5) & a_fluorescent(s2) & Theme(s2,x5) & n_worker(x4) & n_vest(x2) & a_fluorescent(s1) & Theme(s1,x2) & n_worker(x1) & a_down(s3) & Manner(e2,s3) & Actor(e2,x4) & v_sit(e2) & in(x4,x5) & Theme(e1,x3) & Actor(e1,x1) & v_take(e1) & n_break(x3) & in(x1,x2))
exists e1 x1 x2.(n_group(x1) & Theme(e1,x2) & Actor(e1,x1) & v_play(e1) & n_pool(x2))