This is a mistake made purely off OF pronunciation of conjunctions. Then, when the conjunctions are broken down incorrectly into what is supposed to be their original state, the mistake is made.
The mistake of “could of” is a mispronunciation of the conjunction “could’ve.” The broken down conjunction translates to “could have.”
WRONG: I could of gone to the store alone, Mom.
RIGHT: I could have gone to the store alone, Mom.
The mistake of “would of” is a mispronunciation of the conjunction “would’ve.” Once broken down the conjunction translates to “would have.”
WRONG: I would of sent the cake sooner, but you weren’t in the office.
RIGHT: I would have sent the cake sooner, but you weren’t in the office.
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