Axis: descendant-or-self
ElementNode-set
AAA id = a1a1 b1 b2
BBB id = b1b1
BBB id = b2b2
AAA id = a2a2 b3 b4 c1 c2 b5 c3
BBB id = b3b3
BBB id = b4b4
CCC id = c1c1 c2
CCC id = c2c2
BBB id = b5b5 c3
CCC id = c3c3