When carbon is added to iron in the proper proportions , the result is steel.
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Creamoftartar酒石,aweakacid,canbeaddedtoeggwhitestohelpthemfoam泡沫whentheyarebeaten
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InthenortheasternUnitedStates,itrainsintermittently间歇地throughoutthespring.
Formulatedin1823,theMonroeDoctrineassertedthattheAmericaswerenolongeropentoEuropeancolonization.