The word would has a lot of uses in English and can be challenging to master.
To make things easier, let's say there are three major categories:
Using would to talk about the past.
Using would in a hypothetical or conditional situation.
Or using would to be more polite.
As with most things in English, there are a few exceptions that don't fit perfectly into these categories, so we'll call them miscellaneous for now and look at them in a little bit.
Would in the Past
One of the simplest uses of would to talk about the past is when it is used in the same way as used to to describe something that happened regularly.
I would always sneak downstairs for a midnight snack.
This means that, in the past, I used to sneak downstairs for a snack regularly.
Another way we use would in the past is to talk about the future from the perspective of the past.
The boss knew the team would be late.
This is the past tense version of saying: The boss knows the team will be late.
A third way to use would in the past is to talk about someone refusing something.
Here's an example. If Lauren refused to tell you what was wrong, you could say:
Lauren wouldn't tell me what was wrong.
Sometimes things refuse stuff, not just people. How would you say that despite trying a lot of things, the oven refused to work?
No matter what he tried, the oven wouldn't work.
The last usage is when we make guesses about things that happened recently that you're pretty confident in.
For example, If you ordered pizza and somebody just used the doorbell, how might this conversation look?
Who just rang the doorbell? That would be the pizza guy.
Would with Hypotheticals
One category down, two to go. In this next case, we're looking at situations that involve some sort of condition, preference, hypothetical situation, or wish.
The easiest one to use here is would rather, which is how we express our preference between a few alternatives.
How do you say that you prefer to study English instead of Spanish?
I would rather study English than Spanish.
Notice that we use the word than when we specify the thing we compare our preference to.
On the other hand, what if somebody asked for your phone number and you have absolutely no interest in sharing it. You might say…
Can I have your phone number? I would rather die.
The alternative here is implied. I would rather die than give it to you.
You can also use "would rather" in a question to find out somebody's preference. How might you use it here?
Would you rather cook or go out to eat?
Notice that when we use would in a question, the subject and would switch places.
Another common place that would shows up is in conditions with if. This could be a condition that may happen or one that didn't or won't, and we're imagining the outcome.
For example, let's say you live in New York, and your friend lives in California. How do you tell your friend that if they moved to New York, you might visit them?
If you lived here, I would stop by.
This means I believe it is unlikely that you will live here, but it's still a possibility. If you do move here, then I would stop by.
On the other hand, what if your friend already decided to live in California and that no matter what, they will never live in New York. How would you change the sentence?
If you had lived here, I would have stopped by.
We're saying that your friend's decision to live in California happened in the past and is final. We are now imagining what things would be like if they didn't make that decision.
The next usage of would in this category is probably the trickiest of them all. Here is when we use it to talk about possible or fake situations where we can imagine what they would be like. Let's look at some examples.
If your sister asked you to go to Ireland with her, how might you respond?
Want to come with me to Ireland? Really? That would be awesome.
Here we are imagining what might happen, going to Ireland, and what things will be like. They would be awesome.
Next, let's say the hypothetical situation is registering for a class that you want to take. Something is stopping you, though. What might you say?
I would sign up for the class, but I have to work.
Here you are imagining your actions in a hypothetical world where you don't have to work.
The last of the hypothetical usages is to talk about things you wish were different. Maybe because you're annoyed or impatient.
Let's say you are sick of having to work late on Fridays. How can you express this wish with would?
I wish my boss would let me go home early on Fridays.
I wish + would + the verb, let go, lets people know that you are frustrated with this situation and wish it was different.
How about this one where you are annoyed someone doesn't visit you enough.
I wish you would visit me more often.
It's annoying me that you don't visit enough.
Side note, a common point of confusion, is trying to do this same thing with hope instead of wish. With hope, you're talking about something you want, not really a hypothetical situation.You can't say. "I hope you would visit me more often." You either have to say:
I hope you will visit me more often
"I hope you visit me more often."
Would to be Polite
The third group is probably the easiest of the three because all we're doing here is using would to soften our language.
We can form more polite requests
We can give our opinions without sounding too judgmental
Or we can provide advice more gently
Instead of telling someone to come inside, how would you make this request more polite?
Would you come inside?
We change it from a command into a question and start it with would.
Can you think of a way to give your opinion about your boss without being so direct?
What do you think about the new boss?
I would think he'd be smarter.
Instead of just saying he's dumb, we say we would think he would be the opposite, but he's not. In other words, we are turning our opinion into a hypothetical situation.
In the case of advice, we can also soften our suggestions to be more polite and not sound like we commanded someone to do something.
For example, if your coworker complained that "John is being very rude." You could say "tell him to leave," but this sounds pretty blunt or direct. It comes off as if you are annoyed with them complaining. How can you be more polite?
I would tell him to leave.
You can imagine that there's an if I were you at the end of this. I would tell him to leave if I were you. This is much more gentle and makes it seem like you are empathizing with their situation.
I've got some good news. We've made it through the three major categories. I've got some more good news. The miscellaneous stuff is pretty easy to understand. There are only two uses here.
Using would to ask the reason why something happened
Expressing your desires
You can ask:
Why would he lie to me?
to figure out the reason he has to lie.
If you use I or we in the question, it's a way to tell the listener that you have no reason to do something.
If I say "why would I lie?" this means I'm not lying. I have no reason to.
This last one, I'm sure you know very well by now, but how do you say you have a desire to move to the US one day?
I would like to move to the US one day.
Would is a huge topic, and you're not going to master a word with so many usages after reading one article. Now that you know the theory, you need to practice. Start collecting examples from what you see in real life, and try to use it as often as possible to internalize everything.