In French, the relative pronoun où can have two different meanings.
Learn about the relative pronoun où in French
Look at these straightforward examples of où as a relative pronoun:
Here où simply means where and introduces an action taking place in a previously mentioned location.
See also Dans lequel/laquelle : alternative to où with places (French Relative Pronouns)
Now look at these sentences using où in a different context:
This can lead to completely different ways to express things than in English:
Note that you cannot omit the où the way you can the when/that/which in English.
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Examples and resources
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Et l'ombre danse au coin du feu.It's the time when everyone is good,
And the shadow dances near the fire.
The era he lived in was dangerous.