Correct spelling

done

Correct spelling, explanation: done is an irregular past participle of do. As an irregular form, there is no specific rule to adhere to when creating it, as there are already established acceptable forms which are not debatable. While do and done are similar, it is best to remember irregular verbs by heart.

Definition of done:
Verb, past participle
1. Past participle of do
After everything I had done today, I just wanted some rest.
Adjective
1. To be over with something
It’s midnight and I’m still not done with my homework.


Incorrect spelling

doned

Incorrect spelling, explanation: done is already a past form of do, so doned is incorrect because it would be a double past tense. What is more, done is irregular form, while the past-tense suffix -ed is only applicable for the verbs with a regular past tense. When it comes to irregular verbs, it is just the best to memorize them, as there is no rule (such as adding -ed) that is applicable to all of them.