英文關鍵字
bags
central
city
construction
danger
deep
distribution
district
efficiency
energetics
energy
equipment
excavator
flattening
ground
hard
heat
heating
heavy
hydraulics
industry
infrastructure
insulation
investments
line
machinery
maintenance
motion
objects
pipeline
pipes
plastic
protective
reconstruction
repair
safety
saving
sign
steam
structure
system
technology
tubing
underground
work