People watch a musician play the guitar.
People are in a library.
One cannot be in a library and watch a musician play the guitar at the same time.
exists e1 s1 x1 x2 x3.(Theme(e1,x2) & Actor(e1,x1) & v_watch(e1) & n_guitar(x3) & (x2 = x3) & n_play(x2) & a_musician(s1) & Theme(s1,x2) & n_people(x1))
exists p1 x1.(exists x2.(in(x1,x2) & n_library(x2)) & n_people(x1))