With no explanation, label each line with "O", "person-other", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
They
have
two
sons
,
William
and
Edward
.
They:O
have:O
two:O
sons:O
,:O
William:person-other
and:O
Edward:person-other
.:O