英文關鍵字
blocked
building
cleaning
container
control
dirty
engine
environment
equipment
faeces
fecal
feces
full
helmet
hose
industrial
industry
job
maintenance
man
manhole
modern
overall
people
pipe
professional
pump
removal
repair
service
sewage
sewer
sewerage
specialist
stoppage
stream
street
system
tank
tanker
tool
transportation
truck
vehicle
water
well
work
worker
working