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.
over
Preposition
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Something is over when it has finished, usually referring to an event.
When the movie was over we left the movie theater.
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In a location above something.
He stepped over the dog.
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From one side to the other.
They went over the bridge.
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If you invite someone over, you invite them to your house.
They had him over for tea.
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A number divided by another.
Eight over two is four.
over
Noun
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An over in a cricket match is six balls bowled from one end.
The captain told me I would have to bowl the next over.
b
Noun
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B is the second letter of the alphabet.
"b" comes after "a" but before "c"
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In some schools, a B is a fairly high grade.
Charles got a B in his maths test.