Six hundred years ago, people pronounced the K in knight, and GH sounded like the ch in German ich. In Old English, the word was cniht, and every letter was pronounced. Educated speakers stopped pronouncing the K in the 1600s, making knot and not homophones. German kept the sound: Knie still begins with a pronounced K. These letters are fossils of sounds that really were there.
The narration uses a synthetic (AI) voice.
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