A welder person in the middle of a weld.
A person welding
A person welding is in the middle of doing a weld.
exists x1 x2 x3 x4.(n_middle(x3) & a_topic(x1) & in(x1,x3) & of(x3,x4) & n_weld(x4) & n_person(x1) & of(x1,x2) & n_welder(x2))
exists x1 x2.(a_topic(x1) & Time(x1,x2) & n_welding(x2) & n_person(x1))