英文關鍵字
adjusting
attaching
cam
camera
caucasian
cctv
circuit
closed
closedcircuit
construction
contractor
control
detection
drill
electric
electrical
electrician
electronic
equipment
fitting
fixing
guard
home
hotel
inn
install
installation
installing
male
man
monitoring
private
protection
record
repairman
safe
safety
security
service
skill
spy
spying
surveillance
system
technician
technology
video
view
wall
worker