C'est ou il est?

Oh là là - vous devez étudier.

C'est et il est - despite similar meanings, their usage differs.

C'est is used as a modifier or to relate to something already mentioned. C'est la vie ! ... "L'etat, c'est moi" - Louis Quatorze.



Il est or elle est is used with unmodified nouns, or as a reference to an adjective. Voici mon frère - il est étudiant. Il est intelligent.

Il or elle est is a little more formal than c'est, and sometimes their use is interchangeable. Il est (C'est) bon de savoir ce dont on a envie.

For a complete explanation, see About.com: French or just take the test.

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