A cashier at a grocery store.
A cashier is currently working
Just because a cashier at the store doesn't mean they are currently working.
exists x1 x2 x3.(a_topic(x1) & at(x1,x2) & n_store(x2) & of(x2,x3) & n_grocery(x3) & n_cashier(x1))
exists e1 s1 x1.(a_currently(s1) & Manner(e1,s1) & Actor(e1,x1) & v_work(e1) & n_cashier(x1))