英文關鍵字
activity
belt
business
cobblestone
conveyor
crushed
crusher
dark
dig
dust
earth
engineering
equipment
extraction
factory
geology
gravel
ground
heap
heavy
industrial
industrialized
industry
large
loading
lorry
machine
machinery
manufacturing
material
metal
mine
mineral
mining
oil
old
pebble
production
quarry
rock
sand
steel
stone
technology
transportation
work
worksite