With no explanation, label each line with "O", "location-mountain", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
The
eruption
of
the
trachytic
Green
Tuff
Ignimbrite
about
56,000
years
ago
was
followed
by
caldera
formation
.
The:O
eruption:O
of:O
the:O
trachytic:O
Green:location-mountain
Tuff:location-mountain
Ignimbrite:location-mountain
about:O
56,000:O
years:O
ago:O
was:O
followed:O
by:O
caldera:O
formation:O
.:O