英文關鍵字
alarm
background
bomb
business
change
clock
computer
count
countdown
counter
counting
deadline
device
digit
digital
diode
display
down
electric
electronic
element
elevator
end
equipment
indicator
led
level
light
modern
new
number
numbers
numeral
office
panel
pass
remaining
second
set
technology
ten
time
timer
type
watch
year
zero
zeros