We use "would have" and "would not have" to imagine the opposite of what really happened in the past.
Subject + would not have + past participle...
- I wouldn't have come to the party, but she made me come.
(Really, I went to the party, but I didn't want to go. She made me.)
- If I hadn't studied hard, I would have failed the test.
(Really, I studied hard and I passed the test.)
- She would have died if Mark hadn't saved her from drowning.
(Really, she didn't die. Mark saved her from drowning.)
Without an if-statement, this sentence talks about something you did not want to do.
- I wouldn't have come today because I am sick, but I have to give a presentation in the afternoon.
- Mark and Tina wouldn't have broken up, but Mark had to move to San Francisco for his job and Tina had to stay in New York for her job. So, they broke up.
It is very common to use "would (not) have" with an if-statement. We are just imagining the past if something different had happened. If...+ subject + would not have + past participle...
- If I had not studied hard, I wouldn't have passed the test.
- If she had known that he would be here, she wouldn't have come. She hates him.
- If he hadn't been driving and using his phone, he wouldn't have gotten into an accident.
- If humans had never discovered antibiotics, then many more people wouldn't have survived diseases.
We can switch the order of the sentence. Subject + would not have + past participle...+ if...
Bonus Tips and Points
- The company would not have gone bankrupt if they had made better decisions.
- Jon and Steve wouldn't have won if they hadn't cheated. They are big cheaters.
- He wouldn't have gotten the promotion if his father weren't the vice-president.
- They would not have helped you if you hadn't asked them for help.
1. We usually use the past perfect in the "if-statement". The past perfect is "had (not) + past participle".
- If I hadn't been in the park that day, I wouldn't have met her.
- If they had come earlier, they wouldn't have missed the beginning of the movie.
- I would not have enjoyed my time if you had not come.
- We wouldn't have known that if Mark had not told us.
2. It is also okay to use the past tense instead of past perfect in these sentences. Many grammar books say that we cannot use the past tense, but many native English speakers use both. However, it is better to use the past perfect.
Real-World English Conversations
- If I had arrived 10 minutes later, I wouldn't have gotten a seat.
(=If I arrived 10 minutes later, I wouldn't have gotten a seat.)
- She wouldn't have become a manager if she hadn't worked hard.
(=She wouldn't have become a manager if she didn't work hard.)
A) I wouldn't have succeeded if it weren't for my father.
B) What do you mean?
A) My father always helped me and pushed me to be the best.
A) Even if we had had more time, I wouldn't have gone to the museum.
B) Why not?
A) Simply put, I hate museums. If I had had more time, I would have gone to Central Park.
B) That would have been fun, too.
A) I wouldn't have come if I knew that you were going to be in a bad mood.
B) What am I doing?
A) You are being super sarcastic and just not being nice.
B) Sorry. I'll try to be better. I'm just having a rough day.
A) If he had been more careful, then this problem never would have happened.
B) True. But the past is the past.
A) He wouldn't have forgiven me if I had made the mistake. He would have complained and blamed me for weeks.
B) Don't think about what you think he would do. Just do the right thing. Use these free English lessons to learn the most common sentence patterns in the English language. If you learn these sentences and questions, it will help you speak English well. Study the lessons thoroughly, practice making your own sentences, and come back to review often. If you do these three steps, your English speaking will improve quickly and you will be able to have natural English conversations.