With no explanation, label each line with "O", "person-scholar", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
Karl
Marx
expressed
disappointment
at
the
bourgeois
character
of
the
revolutions
.
Karl:person-scholar
Marx:person-scholar
expressed:O
disappointment:O
at:O
the:O
bourgeois:O
character:O
of:O
the:O
revolutions:O
.:O