英文關鍵字
air
auto
automobile
automotive
car
catalyst
catalyzer
converter
cut
dioxide
ecology
element
environment
exhaust
fuel
gas
metal
motor
muffler
neutralizer
noble
old
palladium
part
piping
platinum
pollution
problem
protection
purchase
purification
recovery
recycle
recycling
repair
rhodium
safety
scrap
smog
smoke
soot
system
technology
transportation
vehicle
work