Verbs like ‘would have’ and ‘could have’ are modal verbs. So like other normal verbs, they do not have past forms. Hence, people can talk about the past by adding a past participle after ‘could have’ and ‘would have’ in a sentence. They both almost mean the same thing, but their meanings would completely change if exchanged with each other in a sentence.
Would Have vs Could Have
The main difference between would have and could have is that they can be actually used in both could have and would have, but could have is a bit formal and polite way of saying something compared to could have.
The expression ‘would have’ often is used to ascertain or express the certainty in case of an event or happening. When a person wants to indicate and describe if a certain action happened certainly, then the outcome would have taken place by using would have.
The expression ‘could have’ often is used to denote that something could have possibly happened in the past if a specific thing was done, but a person didn’t do it. It’s a modal of ability.
Comparison Table Between Would Have and Could Have
| Parameters of comparison | Would Have | Could Have |
| Meaning | ‘Would have’ often is used in sentences when we talk about a situation that we only imagine or of things that frequently happen in the past. | ‘Could have’ is mainly used to discuss possible actions or happenings in the present or the future. |
| Situation | It denotes a possible situation | It denotes an imaginary situation. |
| Usage | ‘Would have’ is used in making the request offer and seeking permission. | ‘Could have’ is used in making suggestion, request, or seeking permission. |
| Tense | ‘Would have’ denotes possibility in a sentence. | ‘Could have’ denotes certainty and ability in a sentence. |
| Example | She would attend the meeting if she were well. | She could have finished her homework, but she chose not to. |
What is Would Have?
‘Would have’ is used when a person wants to show if someone wants to do something or not (volition). A person can also use ‘would have’ when they talk about something they wanted, but they didn’t. The term ‘would have’ is used when something almost certain to happen in a normal course did not happen, or something went wrong due to which it did not happen.
Example:
1. I would have eaten breakfast, but I got late for the office.
2. I would have done my homework, but I didn’t understand anything.
3. I would have been late if the bus hadn’t arrived on time.
‘Would have’ is a possibility for an event to happen or not happen due to some external forces which happen. It is used to describe the ability of a sentence. When it comes to requests, we can use both ‘could have’ as ‘would have,’ but ‘could have’ is more formal and polite than ‘would have.’ While making polite requests, ‘could have’ is used with suggestions, indicating a possibility. On the contrary, ‘would have’ is used with offers or invites, because it is more usual.
What is Could Have?
‘Could have’ is used when a person wants to make a confident approximate guess about a specific something that happened in the past. This is a modal of possibility. In this case, the guess a person is making a statement may or may not be true as such. It is just a point of opinion that may have happened. ‘Could have’ is an expression that often is used to describe or express a possibility of something that could have happened. It implies that when people use could have in a sentence, they are implying that there existed a possibility of something happening, but it did not.
Example:
1. You could have attended the party, but you decided not to.
2. I could have stayed up late, but I had my exam the next morning, so, I decided to go early to bed.
3. He could have studied harder, but he was lazy enough, and that’s why he failed the exam.
‘Could have’ is used to denote that something was possible with a fair possibility to fulfill certain conditions. When people talk about the last use could have, we make a reference to things where people could have done in the past, but they chose not to, or they couldn’t. When people talk about possibility, it should be understood that when they say there was a possibility of something happening, the possibility of a thing not going down the way they want to be, is also considered.
Main Differences Between Would Have and Could Have
- ‘Would have’ is used to denote the possibility of something, whereas ‘could have’ is used to indicate certainty or ability of something.
- ‘Would have’ shows a person’s desire to do something, but they could not, whereas ‘could have’ indicates that something was possible in the past, but it didn’t happen.
- ‘Would have’ is used as past tense action, whereas ‘could have’ is used to describe the past tense actions.
- ‘Would have’ is used in a sentence to carry a tone of desire. Whereas ‘could have’ is used to hold a manner of criticism in it.
- ‘Would have’ in a sentence denotes a specific consequence of an unreal condition, whereas ‘could have’ in a particular sentence indicates a possible result of an actual situation.
Conclusion
When it comes to requests, a person surely can use both ‘would have’ and ‘could have,’ but it’s just that would have is a more formal way of putting up a statement as it indicates a sense of possibility. ‘Could have’ is more formal and polite as compared to would. ‘Could have’ is used to suggest seeking permission, whereas ‘would have’ is used to request permission. According to the English dictionary, both words have almost the same meaning, yet their meanings would differ if replaced with each other. Both words should be used carefully regardless in what context it has to be used.
References
- https://www.tandfonline.com/doi/pdf/10.1080/00138383208596592
- https://www.sciencedirect.com/science/article/pii/S0028393213000298