If you want the dictionary definition, just double click on any word.

Hard is an adjective. It can mean solid, industrious, or difficult.

For example:-

Heating the clay makes it hard (solid) .
She is a hard (industrious) worker.
It was a hard (difficult) test.

Hardly is an adverb and means only just or certainly not.

For example:-

The teacher spoke so quietly I could hardly (only just) hear her.
You can hardly (certainly not) expect me to do the test for you!

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