With no explanation, label each line with "O", "other-astronomything", "person-other", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart" or "building-airport" preceded by ":".
It
was
discovered
by
Michel
Giacobini
,
who
observed
it
in
the
constellation
of
Aquarius
on
December
20
,
1900
.
It:O
was:O
discovered:O
by:O
Michel:person-other
Giacobini:person-other
,:O
who:O
observed:O
it:O
in:O
the:O
constellation:O
of:O
Aquarius:other-astronomything
on:O
December:O
20:O
,:O
1900:O
.:O