A person is cropping grass by driving a mechanical grass cutter vehicle
The person is mowing his lawn.
Not all persons driving a Mechanical grass cutter is mowing his lawn.
exists e1 e2 s1 x1 x2 x3 x4 x5.(by(e1,e2) & Theme(e2,x3) & Actor(e2,x1) & v_drive(e2) & n_vehicle(x3) & of(x3,x5) & n_cutter(x5) & of(x3,x4) & n_grass(x4) & a_mechanical(s1) & Theme(s1,x3) & Theme(e1,x2) & Actor(e1,x1) & v_crop(e1) & n_grass(x2) & n_person(x1))
exists e1 x1 x2.(n_lawn(x2) & of(x2,x1) & n_male(x1) & n_person(x1) & Theme(e1,x2) & Actor(e1,x1) & v_mow(e1))