英文關鍵字
aluminum
background
bar
bars
blue
building
chain
close
construction
couple
couplers
cut
cutting
drill
duct
engineering
equipment
factory
focus
gas
girl
grey
grinding
hand
industrial
industry
iron
labor
laptop
left
light
machine
manufacturing
many
metal
moving
pan
pipe
pipes
plastic
pressing
pull
right
rod
safety
securing
slider
spark
steel
tilt
tool
using
valves
warehouse
welding
worker
workers
working