two very muddy men drilling for oil
The guys are working at an oil rig.
Working at an oil rig could mean they are repairing the oil rig. It may not mean they are drilling for oil.
exists e1 s1 x1 x2 x3.(a_topic(x1) & for(e1,x3) & n_oil(x3) & Actor(e1,x2) & v_drill(e1) & (x1 = x2) & n_man(x1) & a_muddy(s1) & Theme(s1,x1) & r_very(x1) & card_eq_2(x1))
exists e1 x1 x2 x3.(n_guy(x1) & at(e1,x2) & n_rig(x2) & of(x2,x3) & n_oil(x3) & Actor(e1,x1) & v_work(e1))