英文關鍵字
barge
bin
boat
can
city
clean
cleaner
cleaning
cleanness
cleanup
condition
dirty
ecology
environment
environmental
equipment
garbage
job
maintain
maintenance
male
man
municipal
municipality
nature
net
occupation
operating
operational
organization
outdoor
pollution
problem
public
river
rubbish
scoop
service
ship
staff
tool
transport
transportation
trash
urban
waste
water
watercraft
work
worker