The correct spelling of knot + ed is knotted.
We add the suffix -ed to the noun knot to form the adjective knotted.
In this case, when adding the suffix -ed there is a change in spelling: we must double the last consonant of the root word.
In general, when adding a suffix that starts with a vowel, we double the last consonant of the root word if:
- it is a long word that ends with a vowel followed by a single consonant:
benefit + -ed → benefitted
prefer + -ing → preferring
- if it is a long word with a strong accent in the last syllable:
forget + -ing → forgetting
regret + -ed → regretted
wed + -ing → wedding
knot + -ed →knotted
You can learn more about suffix -ed in the link below:
https://brainly.com/question/396322
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