Preterite vs Imperfect: Spanish Verb Tenses Demystified

Today we are tackling the dreaded preterite vs imperfect. These two past tenses tend to lead to a lot of difficulty for English speakers, but today we’re going to take them one step at a time and learn how to master them. 

From learning to tell a story to simply talking about something in your past, it’s crucial to be able to use the past tenses correctly. And even though Spanish has around 7 different ways to express the past, these two still remain as troublemakers. 

So today let’s go over each of them individually, then talk about some of their major differences at the end. 

Preterite Tense Explained

Let’s start off strong today and work on the more difficult of the two first. The preterite tense is used to explain past events that took place once. 

It’s similar to the simple past in English (words that end in -ed), but not exactly the same. Most of the time, we talk about the pretérito perfecto simple to describe completed actions that have a definite beginning and end. For example:

• La semana pasada, tuvimos un examen. – Last week, we had an exam.

Here you are giving an exact time in the past and the test probably had an established beginning and end. 

Sounds pretty easy, right? So let’s move on to learning how to form the preterite. 

Preterite Conjugation

We’re starting with the preterite tense first because it’s the more difficult of the two. Not only is the regular conjugation for this verb tense a bit complicated, but there are also a ton of irregular verbs. 

And there’s no better way to learn than by practicing, so here are the regular conjugations:

As you can see, the ER and IR verbs are exactly the same when it comes to conjugation, so that does make life a bit easier! However, the Spanish language has a ton of irregular verbs for the preterite tense. Here are just a few of them:

As you can see here, the irregular verbs will change both in the stem and in the endings. 

The good news is – the preterite is the most irregular verb tense out there, so once you can conquer it, the rest of the Spanish language is yours for the taking. 

The best thing you can do for the Spanish preterite is to start to look out for some patterns and slowly memorize them one at a time. It’s easy to get overwhelmed learning them all at once, so practice makes perfect!

When to use the preterite

Now let’s move away from boring charts and on to the fun stuff! There are four main times when you can use the preterite to describe past actions. Since the preterite tells us that something only happened once or that an action had a definite end, you might start to see some patterns forming.

Specific point in the past

The first use of the preterite is with actions that have a defined ending and beginning. In other words – there’s no ambiguity being expressed because we’re talking about a specific point in time. Here are some examples:

• Ayer por la tarde fui al cine. – Yesterday afternoon I went to the movie theater.
• La película empezó a las cinco. – The movie started at five.

In both of these examples, we’re specifically using words that express time (ayer, a las cinco), but they aren’t necessary. The preterite is already referring to a point in the past, but we’re just being more specific here. So remember that as we continue forward. 

Specific period of time 

The preterite can also refer to a longer point in the past, such as periods of time. What’s important is that we are being concrete and specific about our timeframe. So we can also talk about actions in the past like this:

• Estuve en la cola durante tres horas. – I was in line for three hours.
• Caminamos dos horas. – We walked for two hours.

Again, even though we’re listing a period of time – it still has a defined beginning and end. 

List of actions

Next, whenever you want to list a series of completed events, you would use the preterite tense. Just being a list isn’t enough – it has to be a list of actions with a beginning and end. 

• Ayer fui al mercado, compré pan y volví a casa. – Yesterday I went to the market, bought bread, and came home.

So even though you can have a list of actions with the imperfect, the preterite tells us that all these events occurred at a clearly defined point in time. 

Sudden action

Finally, when something suddenly happens we’re going to use – you guessed it – the preterite. That’s because it’s emphasizing that point in time when the action occurred. For example:

• Estaba caminando cuando vi una serpiente – I was walking when I saw the snake
• Estaban durmiendo y de repente sonó la alarma – They were sleeping and suddenly the alarm went off

As you might have noticed – many times this is preceded by a verb in the imperfect tense – but more on that in a minute. 

Preterite Trigger Words

So now it’s time to find out about some trigger words that should be a big red flag to you as a learner. Since all of these words are implying a specific moment in the past, you’ll naturally use the preterite tense. So if you see these – you’ll probably use the preterite.

Now, remember – this isn’t a 100% fool-proof method. More like 90% of the time. Because you know, we can’t make grammar too simple, right?  

• Anoche – Last night
• Ayer – Yesterday 
• La semana pasada – Last week 
• El mes pasado – Last month 
• El año pasado –  Last year 
• En ese momento – At that moment 
• El otro día – The other day
• Una vez – One time 
• Durante X – For X (time)

So the next time you use any of these time markers – consider using the preterite. Now it’s time to move on to the next of the past verb tenses, the imperfect tense. 

Imperfect Tense Explained

The imperfect tense can be seen as the opposite of the preterite. If the preterite describes clear events with a defined beginning, then the imperfect will give background information and talk about things that don’t unambiguously begin or end. 

This is really common to talk about conditions, ages, long periods of time, repeated events, and just general narrative-style information. 

But first – let’s look at how to form the imperfect. 

Imperfect Conjugation

We already mentioned that between the two different past tenses, the imperfect is absolutely the easier one. This is especially true when it comes to conjugation. Take a look at the conjugation chart:

The preterite and the imperfect share another common trait: the ER and IR verbs have the same conjugations in each of their respective tenses.

And are you ready for the best news of all? 

There are only THREE (3) irregular verbs! Ser, ver, and ir are the only ones you need to worry about. 

Just that is cause for celebration.

When to use the imperfect tense

The Spanish grammar rules for the imperfect tense are just as clear as for the preterite. In theory, you could always just memorize the rules for one of them at first, then decide which to use based on the process of elimination. 

But it’s always better to be over-prepared than under-prepared. So here are the three main times you can use the imperfect. 

Undefined beginning or end

If it’s not very clear when something starts or ends – or when the time isn’t important to the sentence, we can use the imperfect. Check out these examples of the imperfect tense:

• Antes, yo corría más. – Before, I used to run more.
• Cuando era niña, tocaba el piano. – When she was a girl, she played the piano.

In the first example, you’re just saying “before”. That means just some point in the past – but it’s not really important to be specific. And in the second example, being a child doesn’t have a very clear beginning and end, so we’ll use the imperfect.

Background info

This next usage of the imperfect is great for the next time you need to tell a story. Basically, any time you want to give information about a past event – but you’re not focused on the time – then you use the imperfect. For example:

• Era un día precioso. – It was a beautiful day.
• María cocinaba mientras su madre leía las noticias. – María was cooking while her mother was reading the news.

Repeated events

Finally, when you want to explain that something happened repeatedly over a period of time, we’ll use the imperfect. This is one of the biggest differences for the preterite vs imperfect, so make sure to write this one down! Here are a few examples:

• Todos los días hacía deporte. – He exercised every day.
• Algunas veces cocinaba una tarta. – Sometimes he would bake a cake. 

So even for things that are in a list – if they are repeated actions over time, then we need to use the imperfect.

Imperfect Tense Triggers 

Just like in the preterite – there are a few words that can trigger the Imperfect Red Flag Alert. So if you see any of these words, there’s a good chance you should be using it. 

• Todo el tiempo – All the time
• Muchas veces – Many times 
• Cada día – Every day 
• De vez en cuando – Once in a while 
• Por un rato – For a while
• Mientras – Meanwhile 
• Nunca – Never 
• Siempre – Always 
• En aquella época – In those times 
• Todos los años – Every year 
• Todos los días – Every day 

Verbs that change meaning

Before heading off, there’s one last thing you should know about the preterite vs imperfect. And that is five specific verbs that will change their meaning drastically depending on the tense. 

But the truth is, all verbs undergo a similar conceptual change. However, we have direct translations for these five verbs in English that make it a lot easier for you to understand the whole topic. 

So pay attention to these five verbs and let them help you master the topic! 

A Definite End

Just like the preterite, this article has a definite beginning and end. Luckily for you, you can go back and read it as many times as you need until you master the preterite vs imperfect. 

And in the meantime, go ahead and sign up for a free private class or a 7-day free trial of our group classes to practice what you learned!