英文關鍵字
gear
cog
motion
maintenance
worker
alpha
channel
rotate
work
perpetuum
mobile
running
wheel
engine
design
black
background
concept
bond
spares
interlock
connect
machine
mechanical
mechanism
metallic
teeth
working
silver
shiny
precision
people
manufacturing
rotation
power
machinery
turn
grey
conceptual
teamwork
cooperation
collaboration
engineering
steel
industry
cogwheel
component