英文關鍵字
aluminum
background
bar
bars
big
building
bundle
carry
construction
couple
crane
cutting
drill
duct
engineering
equipment
factory
grinding
helping
industrial
industry
iron
labor
left
light
liquid
machine
manufacturing
metal
pipe
pipes
red
right
rod
safety
silver
slider
spark
splashing
steel
tilt
tool
trolly
two
warehouse
welding
white
worker
workers
working
yellow