Two identical people are completing different tasks.
Twins are working.
not all working twins are needed to have different tasks
exists e1 s1 x1 x2 x3.(n_task(x3) & Theme(e1,x2) & Actor(e1,x1) & v_complete(e1) & -(x2 = x3) & n_task(x2) & n_people(x1) & a_identical(s1) & Theme(s1,x1) & card_eq_2(x1))
exists e1 x1.(Actor(e1,x1) & v_work(e1) & n_twin(x1))