英文關鍵字
256
alarm
background
black
button
control
countdown
counter
deadline
design
dial
digit
digital
display
electronic
emergency
equipment
factory
finger
hand
industrial
industry
machine
modern
monitor
number
object
off
panel
plastic
power
press
process
red
reset
round
safety
set
sign
signal
speed
start
stop
switch
symbol
technology
time
timer
watch
work