Englishfor English speakers
helicopter
Noun
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A helicopter is a type of aircraft. It does not have wings, but has two or more long blades which rotate. It is able to move in any direction, forward or back, up or down, or stay in one place.
The helicopter flew over the sea and was able to land on the ship.
unit
Noun
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One of a measure of something; the amount of something that is counted as "one".
Measure five units to the left.
$4 is the unit price.
A pound is a useful unit for thinking about amounts of butter.
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Form of measurement.
I prefer metric units.
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Item, used when no other word for something exists.
He set up the A/C unit.