英文關鍵字
aluminum
automation
metallurgical
business
construction
crane
ecology
energy
engine
engineering
equipment
factory
floor
gears
gray
harmful
heavy
industrial
iron
loader
machine
man
machinery
manufacture
manufacturing
metal
mill
plant
power
processing
production
roller
roof
rolling
samara
steel
steam
smoke
technical
technology
tool
work
workshop
time
lapse
timelapse
wide
wideangle