英文關鍵字
plastic
work
pipeline
trench
construction
line
industry
worker
industrial
ground
field
equipment
earth
technology
tube
underground
dig
excavation
pipe
gas
site
installation
ditch
connect
conduit
communication
cockpit
cabling
electrician
build
digging
steel
professional
danger
machine
heavy
engineering
cable
electric
large
corrugated
wire
electrical
corrugation
connection
foundation
laying