They are built of twigs and grass and much excrement, often on the remains of previous years' nests and are found in a variety of sites, from well-protected rock caves to exposed ledges.
(They; are built; of twigs and grass and much excrement) (They; are found; L:in a variety of sites, from well-protected rock caves to exposed ledges)
They They
are built are found
of twigs and grass and much excrement
L:in a variety of sites, from well-protected rock caves to exposed ledges