Dialects are different from accents in that

A、Accentsarevariationswithinalanguage,whiledialectsarevariationsacrosslanguages.;
B、Peoplewhospeakdifferentaccentscanunderstandeachotherwell,whilepeoplewhospeakdifferentdialectscannotcommunicate.;
C、Dialectsresultfromgeographicandhistoricaldifferences,whileaccentsaremoreindependentoftheseinfluences.;
D、Whereasaccentsrefertodistinctivepronunciation,dialectreferstospokengrammarandvocabularyaswell.