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.
takeoff
Noun
—
The takeoff is when an airplane moves from the ground into the air.
Put on your seat belt to be ready for takeoff.
on
Preposition
—
positioned at the upper surface of, touching from above
The apple is on the table.
—
at the date of
Tim was born on the 4th of July.
—
along, forwards (continuing an action)
drive on, rock on
—
about, dealing with the subject of
I have a book on history.
There was a World Summit on the Information Society a few weeks ago.
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touching; hanging from
I have no money on me at the moment.
I would like to eat the fruit on the trees.
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because of, due to
He was arrested on suspicion of bribery.
I contacted Joanne on a hunch that she would know about it.
The stock price increased on news of a new product.
on
Adjective
—
If something is on, it is active, functioning or operating.
The television is on.
The lights are on, so it is very bright.