機器
environmental
conservation
crane
dirty
dump
eco friendly
environment
equipment
excavator
factory
garbage
greenhouse effect
heap
industrial
industry
iron
junk
junk yard
junkyard
loader
machinery
magnet
metal
old
pile
pollution
recycle
recycling
recycling center
reduce waste
rubbish
rust
rusty
salvage
scrap
scrap yard
stack
steel
trash
waste
yard