With no explanation, label each line with "building-other", "O", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
Before
Burj
Khalifa
was
completed
,
Willis
Tower
led
in
the
height-to-tip
category
with
after
its
antenna
was
extended
in
2000
,
making
Willis
Tower
slightly
taller
height-to-tip
than
the
WTC
north
tower
's
antenna
that
measured
.
Before:O
Burj:building-other
Khalifa:building-other
was:O
completed:O
,:O
Willis:building-other
Tower:building-other
led:O
in:O
the:O
height-to-tip:O
category:O
with:O
after:O
its:O
antenna:O
was:O
extended:O
in:O
2000:O
,:O
making:O
Willis:building-other
Tower:building-other
slightly:O
taller:O
height-to-tip:O
than:O
the:O
WTC:building-other
north:O
tower:O
's:O
antenna:O
that:O
measured:O
.:O