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".
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In some schools, an A is a very high grade.
Ron got an A on his earth science test.
hundred
Determiner
—
(ordinal hundredth) The number 100.
There are a hundred centimeters in a meter.
hundred
Noun
—
The number 100.
Ten tens is a hundred.
and
Conjunction
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You use and to talk about two things at once.
I like singing and reading.
Mary and Jane went on a holiday together.
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You use and when you are listing a few things and you are now on your last item of the list.
I like singing, reading, cycling and playing soccer.
I used to like this girl from my class as she is pretty, gentle and caring.
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And is used when you are putting two sentences together.
She came into the store, shouted at the cashier, and left.
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Used to show what happened after something else.
The alarm went off and I woke up.
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And is used to join certain numbers together.
Two hundred and thirty-five people went missing after the earthquake.
fifty
Determiner
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(ordinal fiftieth) The number 50.
There were fifty people in my class.
fifty
Noun
—
The number 50.
tens is fifty.