When we express regret, we often use the phrases could have, should have, or would have in our sentences to explain how things might have been different if something other than what happened had occurred.
These terms are fairly straightforward in their definition and use, but for English language learners, the slight nuances of each can be confusing. Below, we quickly review what each means and how to use them in sentences. Then you can practice with some exercises to ensure you fully understand their use.
Modals of Lost Opportunity
Could have, should have, and would have are referred to as “modals of lost opportunity” since they describe scenarios that one wishes had occurred if the past had turned out differently.
In order to fully understand how these terms are used in the past tense, understanding the small nuances between could, should, and would is important.
How to Use Should
Use should when you want to provide a recommendation or advice.
- If you want to pass the class, you should hire a tutor.
How to Use Could
Use could when you want to explore the possibilities of something.
- We could spend the day at the beach tomorrow if you want!
How to Use Would
Use would when you imagine the results of an action or situation.
- We would like to adopt a dog from the shelter this month.
Could Have vs. Should Have vs. Would Have
These terms all relate to past scenarios that never occurred but include slight nuances in their use. You can also use the contractions of each without changing their meaning: could’ve, should’ve, and would’ve. Contractions are commonly used in speech.
How to Use Could Have
The phrase could have helps express possibilities of the past if different decisions or actions had been taken. It is almost always used with an “if clause” to express the past situation as an impossibility, but it isn’t required for correctness.
- She could have helped us with our homework.
- If you had arrived earlier, you could have had dinner with us.
How to Use Should Have
Should have is used to say that a different action should have occurred in the past. It also can be used to suggest that a different action in the past would have been a better choice.
- I should have picked up dinner on the way home from work.
- I should have studied more for that test.
- I should have tied my shoes to avoid tripping.
How to Use Would Have
The phrase would have is used to express two very different things.
You can use would have to express a result of something if things in the past had been different.
- If you had paid attention to the directions, you wouldn’t have failed the exam.
- If I hadn’t eaten such a big dinner, I would have ordered a pizza with you.
You can also use it to emphasize certainty about a result that might have been under different circumstances.
- If I had finished the marathon, I would have qualified for the next race.