英文關鍵字
activity
belt
business
carry
construction
conveyor
crusher
day
dig
digger
elevator
engineering
environment
equipment
excavation
excavator
exterior
extraction
factory
geology
heap
heavy
industrial
industrialized
industry
large
loading
machine
machinery
manufacturing
material
mine
mineral
production
quarry
quarrying
resource
sand
stack
steel
technology
tractor
transport
transportation
vehicle
work