英文關鍵字
barbwire
barrier
bars
boundary
brick
cage
camp
captivity
cell
chain
circles
convict
crime
criminal
danger
defense
empty
enclosure
escape
exterior
facility
fence
forbidden
guard
imprisonment
iron
jail
jailhouse
justice
keep
metal
nobody
obstruction
old
penitentiary
prison
protect
protection
punishment
safety
secure
security
sentence
sharp
sky
steel
stone
trapped
wall
wire