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 ":".
Since
1985
a
solar
thermal
system
using
this
principle
has
been
in
full
operation
in
California
in
the
United
States
.
Since:O
1985:O
a:O
solar:O
thermal:O
system:O
using:O
this:O
principle:O
has:O
been:O
in:O
full:O
operation:O
in:O
California:location-GPE
in:O
the:O
United:location-GPE
States:location-GPE
.:O