英文關鍵字
accident
activity
are
being
breakthrough
city
cold
communication
connections
construction
crane
development
digger
district
ecology
efficiency
energy
engineering
environment
equipment
excavation
ground
heating
heavy
home
housing
hydraulic
industry
installation
installing
insulated
insulation
laying
men
metal
municipal
new
pipe
pipeline
pipes
piping
plumbing
prepared
public
repair
replacing
sewerage
street
substitution
system
tool
trench
tubing
underground
utilities
water
work