Englishfor English speakers
a
Determinative
—
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".
—
In some schools, an A is a very high grade.
Ron got an A on his earth science test.
thousand
Determiner
—
(ordinal thousandth) The number 1,000.
Julius Caesar lived about two thousand years ago.
thousand
Noun
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The number 1,000.
acres
—
noun
(= estate, land)
extensive landed property (especially in the country) retained by the owner for his own use
the family owned a large estate on Long Island