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to plant plant planting planted
dirty air electric power atomic energy burning waste
factories and clouds cars and oil smoke and fumes waste burned on ocean floors
to keep keeping keep keeps
keep planes from :flying bury sand on ocean floors stop air pollution burn leaves without smoke
filled with clean water before operation keep air cushion in oil collecting space during running check oil level during running clean inner separator with low pressure stream
They go only a short way. They are easier to keep clean. Electric power has no smoke. Electric cars need no energy.
They go only a short way. They are easier to keep clean. Electric power has no smoke. Electric cars need no energy.
To keep them dry，and thus easier to clean To remove fuel vapors which are heavier than air To provide adequate air to the engines To cool the machinery areas "
stopping air pollution is hard dirty air is blown away by the wind planes cannot fly through smoke it is impossible to make dirty air cleaner
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