英文關鍵字
background
barrel
blue
business
can
chemical
cold
color
conveyor
design
empty
equipment
factories
factory
gray
grey
heavy
indoor
industrial
industry
line
liquid
machine
machinery
manufacturing
metal
nobody
operation
operative
paint
paper
plant
process
processing
production
protective
quiet
roller
rolling
safety
steel
still
technology
tin
varnish
wall
white
work
worker
yellow