Key Reason for the Mistake: Mishearing “Could’ve”

The mistake arises because “could have” is often contracted to “could’ve” in spoken English, which sounds like “could of” when said aloud. However, “could’ve” is a contraction, where “have” is the correct auxiliary verb for forming past modal expressions. “Of” is a preposition, so it doesn’t fit grammatically in this structure.

Why “Could Have” is Correct

1. Meaning and Grammar
   • “Could have” expresses a possibility or ability in the past. For example, “I could have gone to the concert” means there was a possibility or option to go to the concert, but it didn’t happen.
   • In this phrase, “could” is a modal verb, and “have” is used to indicate a past opportunity or action. This is a common construction with modals, including “should have” and “would have.”
2. “Of” Doesn’t Function as an Auxiliary Verb
   • “Of” is a preposition, used to show relationships between parts of a sentence, like possession or part-whole relationships (e.g., “the color of the sky”).
   • It cannot act as a helper or auxiliary verb, which is why using “could of” creates an ungrammatical phrase.

Examples to Show the Difference

As you can see, “could have” works as part of a complete structure indicating past possibility, while “could of” simply doesn’t fit.

Learning Tip: Recognize the Contraction “Could’ve”

To remember this, think of “could’ve” as short for “could have” and avoid writing it as “could of.” You can mentally expand the contraction when writing or checking your work.

Practice Time

Try filling in the blanks with the correct form:

1. You ________ (could have / could of) won the race if you practiced more.
2. I ________ (could have / could of) arrived earlier, but there was traffic.
3. They ________ (could have / could of) told us about the meeting change.

Answers:

1. could have
2. could have
3. could have