英文關鍵字
background
barb
barbed
barbwire
barrier
block
border
boundary
cage
chain
crime
danger
defend
fence
forbid
forbidden
freedom
gate
guard
imprisoned
iron
isolated
jail
metal
military
outdoor
pattern
prison
prisoner
private
protection
protective
rusty
safety
security
sharp
silhouette
spike
steel
terrorism
war
warning
white
wire