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 ":".
ESWL
involves
the
use
of
a
lithotriptor
machine
to
deliver
externally
applied
,
focused
,
high-intensity
pulses
of
ultrasonic
energy
to
cause
fragmentation
of
a
stone
over
a
period
of
around
30–60
minutes
.
ESWL:O
involves:O
the:O
use:O
of:O
a:O
lithotriptor:O
machine:O
to:O
deliver:O
externally:O
applied:O
,:O
focused:O
,:O
high-intensity:O
pulses:O
of:O
ultrasonic:O
energy:O
to:O
cause:O
fragmentation:O
of:O
a:O
stone:O
over:O
a:O
period:O
of:O
around:O
30–60:O
minutes:O
.:O