Question

1. Paris is the capital of France.
2. Paris is a capital of France.
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Sentence 1 is right. Sentence 2 is wrong. By the way, why do we have to use 'the' before 'capital'? Is that because 'the capital of France ' is the only one in the world of in France?

Answer 1

Yes. There is only one capital in a country, therefore the use of "the." The use of "a" implies there's more than one!