Cada uno es rey en su casa

Meaning: Everyone is in charge in their own home.

Literally: Each man is king in his own house

Example: “En mi casa pongo yo las normas. Cada uno es rey en su casa.” — In my house I make the rules: a man's home is his castle.

Equivalents in English, French, German, and Polish

English: A man's home is his castle
French: Charbonnier est maître chez soi (literally: The charcoal burner is master in his own home)
German: Mein Haus ist meine Burg (literally: My house is my castle)
Polish: Szlachcic na zagrodzie równy wojewodzie (literally: A nobleman on his own farm is the equal of a governor)

Origin: Each person is king in his own house, the Spanish counterpart of the French charbonnier est maître chez soi.

Words that look familiar in another language but mean something else entirely.

Once Actually means 'eleven'. For once (one time), say una vez.
Vaso Actually means 'a drinking glass'. A vase (for flowers) is un jarrón or florero.
Embarazada Actually means 'pregnant'. For embarrassed, say avergonzado/a.

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