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.
bis
adverb
—
Twice; showing that something is, or is to be, repeated, such as a passage of music, or an item in accounts.
z
Noun
—
Z is the twenty-sixth (26th), and last letter of the alphabet.
"z" comes after "y"