A surgeon calibrates his machinery.
The surgeon always calibrates before a surgery.
There is nothing to indicate that the surgeon calibrates before surgery.
exists e1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_calibrate(e1) & n_machinery(x2) & of(x2,x1) & n_male(x1) & n_surgeon(x1))
exists e1 s1 x1 x2.(n_surgeon(x1) & a_always(s1) & Manner(e1,s1) & before(e1,x2) & n_surgery(x2) & Actor(e1,x1) & v_calibrate(e1))