妖しい
怪しい
alertness
away
cam
camera
cctv
cement
circuit
city
closed
control
crime
criminality
deterrent
electrical
electronic
electronics
equipment
guard
industry
instrument
insurance
larceny
monitoring
observe
optical
order
privacy
protect
protection
record
robbery
safe
safety
secrecy
security
spy
surveillance
suspicion
system
technology
television
terrorism
thief
tv
video
visual
wall
warning
watching