英文關鍵字
accident
actions
alarm
alertness
beat
block
buzzer
click
closeup
color
computer
concepts
control
danger
electricity
emergency
equipment
finger
fire
fist
hand
help
hitting
human
ideas
industry
internet
knob
objects
off
operating
panic
people
power
push
red
safety
security
services
sign
simplicity
stop
switch
symbols
system
technology
thumb
touching
urgency
warning