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general::
Phrase(s): When in Rome(, do as the Romans do).
Prov. Behave however the people around you behave. Adapt yourself to the customs of the places you visit. • Jill: Everyone in my new office dresses so casually. Should I dress that way, too? Jane: By all means. When in Rome, do as the Romans do.
McGrawhill's American Idioms And Phrasal Verbs