they are two or more elements that are chemically combined
No, "thankful" is not a compound noun. It is an adjective that describes someone who is grateful or appreciative.
compound
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Yes, if the meaning of the compound word describes one object/thing.
No, "hopeful" is not a compound noun. It is an adjective that describes someone who is full of hope or optimism.
No, the word "tenacious" is not a compound word. It is a standalone adjective that describes someone who is persistent and determined.
Covalent Network
I think that it is chemical formula.
No, the word "fragile" is an adjective, not a compound noun. It describes something that is delicate or easily broken.
Atoms in one compound switch places with atoms in another compound.
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The compound word airborne is an adjective that describes a noun as conveyed by or through the air.Example: We monitor the airborne pollutants.