With no explanation, label each line with "O", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport", "building-hospital" or "building-hotel" preceded by ":".
To
obtain
cyclopentadiene
monomer
,
commercial
dicyclopentadiene
is
cracked
by
heating
to
around
180
°C
.
To:O
obtain:O
cyclopentadiene:O
monomer:O
,:O
commercial:O
dicyclopentadiene:O
is:O
cracked:O
by:O
heating:O
to:O
around:O
180:O
°C:O
.:O