With no explanation, label each line with "location-GPE", "O", "art-broadcastprogram", "art-film", "art-music", "art-other", "art-painting", "art-writtenart", "building-airport" or "building-hospital" preceded by ":".
By
June
2017
,
Raqqa
remained
the
only
major
Syrian
city
fully
under
ISIL
control
and
was
,
therefore
,
its
effective
center
of
operations
.
By:O
June:O
2017:O
,:O
Raqqa:location-GPE
remained:O
the:O
only:O
major:O
Syrian:location-GPE
city:O
fully:O
under:O
ISIL:location-GPE
control:O
and:O
was:O
,:O
therefore:O
,:O
its:O
effective:O
center:O
of:O
operations:O
.:O