Is it a king or the king?

It depends on the context in which the phrase is used.

If you are talking about a specific king, then you would use “the king.” For example, “The king is coming to visit.”

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If you are talking about a general concept of kingship or a role that someone might hold, then you would use “a king.” For example, “He wants to be a king.”

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“I read a book about a king who ruled a large kingdom.” (In this sentence, “a king” refers to a general concept of kingship and is not specific to any particular king.)

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“The king of this country is very popular.” (In this sentence, “the king” refers to a specific person who is the king of a particular country.)

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“She was married to a king, but he was not the king of any country.” (In this sentence, “a king” refers to a specific person who held the title of king, but he was not the ruling monarch of any country.)

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In the game of chess, the king is the most powerful piece.” (In this sentence, “the king” refers to the specific piece in the game of chess.)

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“The king was very pleased with the gift that his subjects gave him.” (In this sentence, “the king” refers to a specific person who is the ruling monarch.)

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“She dreamed of one day marrying a king and becoming a queen.” (In this sentence, “a king” refers to a general concept of kingship and is not specific to any particular king.)

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I hope these examples help to clarify the difference between “a king” and “the king.”

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Learn more.

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