With no explanation, label each line with "O", "other-biologything", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
In
contrast
,
purified
RNA
of
a
negative-sense
virus
is
not
infectious
by
itself
as
it
needs
to
be
transcribed
into
positive-sense
RNA
;
each
virion
can
be
transcribed
to
several
positive-sense
RNAs
.
In:O
contrast:O
,:O
purified:O
RNA:other-biologything
of:O
a:O
negative-sense:O
virus:O
is:O
not:O
infectious:O
by:O
itself:O
as:O
it:O
needs:O
to:O
be:O
transcribed:O
into:O
positive-sense:other-biologything
RNA:other-biologything
;:O
each:O
virion:O
can:O
be:O
transcribed:O
to:O
several:O
positive-sense:O
RNAs:other-biologything
.:O