Englishfor English speakers
breakthrough
Noun
—
A breakthrough is a sudden change, a change from not being able to do something to being able to do something.
After the breakthrough, rubber could be made in a factory and rubber trees were no longer the only source of rubber.
of
Preposition
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Made using.
It is a house of cards.
working
Noun
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The workings of something is how it functions.
He showed us the machine's inner workings.
medium
Adjective
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A medium amount is an amount that is not small and not large, but in the middle.
Would you like a small, medium or large drink?
medium
Noun
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A medium is stuff that something moves through.
Light can go through different media: air, water, glass.
Sound waves slow down when they go through this kind of medium.
—
A medium is a person who hears ideas that come from people who are dead.
We all closed our eyes, and the medium said "I hear your father speaking."
I don't believe those mediums can really hear anything.