air
alternative
animal
computer
conserve
consumption
copper
cotton
crop
cultivation
earth
eat
energy
energy source
fossil
fuel
gas
german
germany
inorganic
internet
key
keyboard
metal
minerals
mining
natural
natural resource
oil
online
ore
organic
production
promotion
regeneierbarkeit
renewable
resource
resources
salt
save
savings
soil guess bodenschatz
sun
tin
uranium
vegetable
water