Englishfor English speakers
a
Determinative
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A is used when the following word could be any of a certain type.
Compare "A book I saw on the shelf" and "The book I gave you yesterday".
a
Noun
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A is the first letter of the alphabet.
The letter "a" comes before "b".
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In some schools, an A is a very high grade.
Ron got an A on his earth science test.
Christmas
Proper noun
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Christmas is a Christian holiday to celebrate the birth of Christ, usually on Dec. 25.
Santa put lots of presents under the Christmas tree.
I've got a week's holiday around Christmas time.
cantata
—
noun
a musical composition for voices and orchestra based on a religious text