Workers on a roof install new shingles.
The workers on the roof are riping off shingles.
install refers to placing shingles, ripping off refers to removing them.
exists e1 s1 x1 x2 x3.(Theme(e1,x3) & Actor(e1,x1) & v_install(e1) & n_shingle(x3) & a_new(s1) & Theme(s1,x3) & on(x1,x2) & n_roof(x2) & n_worker(x1))
exists e1 s1 x1 x2 x3.(n_roof(x2) & n_worker(x1) & a_off(s1) & Manner(e1,s1) & Theme(e1,x3) & Actor(e1,x1) & v_rip(e1) & n_shingle(x3) & on(x1,x2))