How To Use The Japanese Past Tense Like A Pro

Whether you've been learning Japanese for some time or are just starting out into the vast world of this interesting foreign language, you may have encountered the many conjugations that pieces of the language—such as verbs and adjectives—can go through.

Some of the most common conjugations involve changing verbs and adjectives to the Japanese past tense or future tenses.

The good news is that Japanese is a very predictable language, by and large, which means that if you can just commit some basic rules to memory, you will be able to conjugate any word at any time. That includes forming past tense Japanese verbs.

What Is The Japanese Past Tense?

Before we dive into how to form the past tense in Japanese, it’s important to take a moment to ensure that everyone is on the same page about what the past tense actually is.

When talking about the past tense, we mean describing an action or state that occurred historically or chronologically in the past. You can see this happen in English in sentences such as “the dog jumped” and “he was happy.”

“Jumped” and “was” are the past tense form of the verbs; their present tense forms would be “jump” and “is”. Past tense Japanese verbs take a slightly different approach in how they are formed.

Verbs are very much the same; you take a verb, change the end of it a bit, and voilà! However, where Japanese diverges from English is that it also conjugates adjectives.

Adjectives are descriptive words. In English, the word “happy” is an adjective, and English speakers would use “is”—or rather, “was”—to describe being happy in the past tense. However, in Japanese, it is the adjectives and not the verbs that are conjugated in situations like this.

We’ll get to that in a bit.

Conjugating Japanese Verbs Into Past Tense

The main reason to learn how to conjugate the past tense in Japanese is so that you can change your Japanese verbs to reflect past actions or states of being.

However, there are two broad categories of verbs in Japanese: those that end in masu (the most common kind), and desu (which is, well, “is”).

Each of these categories are handled differently, and they change again when shifting from formal to casual. Still, the rules are rather simple, so don’t be discouraged!

Why Use The Formal Past Tense?

As you know, the Japanese language has a heavy focus on the formal form of the verbs. So when you learn the past tense variation of the verb, it's best you know the formal past tense version.

Once you've mastered that, you can start practicing the informal past tense.

Masu Verbs

Masu verbs are those that, as you may have guessed, end in –masu. You use the masu form of the verb to make it polite and to interact with people you don't know.

You’ll need to understand the difference between verb types like U verbs and Ru verbs, but you’ve likely already started on that process if you can get to the –masu part of conjugation.

Once you can create a verb that ends in –masu, changing the masu form to the past tense is easy peasy.

• Masu > Mashita
• Masen > Masen deshita

That’s all there is to making the formal past tense with Japanese verbs!

If you want to say that something did happen in the past (that is, in the affirmative), just change your masu to mashita.

If you would like to say that something did not happen (that is, the negative forms), your masen becomes masen deshita. 

• I listen to music.
  • Ongaku wo kikimasu.
    • 音楽を聴きます。

• I listened to music.
  • Ongaku wo kikimashita.
    • 音楽を聴きました。

• I don’t listen to music.
  • Ongaku wo kikimasen.
    • 音楽を聴きません。

• Now for the past negative form: I didn’t listen to music.
  • Ongaku wo kikimasen deshita.
    • 音楽を聴きませんでした。

Easy, right? Every single masu verb works like that, so if you know how to take a verb and put –masu onto it, you know enough to make past tense Japanese verbs too!

Ichidanる-verbs

An ichidan verb is a verb with いる or える as the ending in their dictionary form.

Even though some verbs ending in いる or える exist that are not ichidan verbs, we can safely say that all ichidan verbs end in いる or える in their dictionary form.

To make the formal past tense of an ichidan verb, you need to remove theる and add ました.

So for example:

• I eat sushi.
  • Sushi wo taberu.
    • 寿司を食べる。

Would become:

• I ate sushi.
  • Sushi wo tabemashita.
    • 寿司を食べました。

If you want to create the informal past tense with ichidan verbs, you only need to replace the last syllable る with た.

• I ate sushi.
  • Sushi wo tabeta.
    • 寿司を食べた。

Desu As A Verb

As a verb, desu means “is” or is the verb indicating a state of being.

It’s even easier to conjugate desu, because it’s a word all on its own—you never need to worry about how to attach the desu ending to another word like you do with masu!

So if you memorise all of the forms of desu, you can change to its past tense at any time, on the fly. And even better—you might recognise one of these forms from the –masu conjugations you just learned! Way to get a head start.

• I am a student.
  • Gakusei desu.
    • 学生です。

• I was a student.
  • Gakusei deshita.
    • 学生でした。

• I am not a student.
  • Gakusei dewa arimasen
    • 学生ではありません。

• I was not a student.
  • Gakusei dewa arimasen deshita.
    • 学生ではありませんでした。

As you can see, it’s just a matter of learning a couple of words and you can suddenly change any idea from the present form to the past tense!

Conjugating Japanese Adjectives Into The Past Tense

One of the many things that separates Japanese grammar from English is how it approaches adjectives.

Adjectives—or words like “blue”, “happy”, “big”, and “surprising”—describe another word, or more specifically, a noun. That’s a person, place, thing, or idea. In English, speakers use “was” to describe adjectives in the past.

However, in the Japanese language, adjectives themselves can be conjugated! In order to determine which type of adjective you’re working with, you’ll need to do a bit of study on the two types of Japanese adjectives.

That’s a separate topic. Once you’ve determined which kind of adjective you’d like to conjugate, just follow these simple rules!

I-Adjectives

I-adjectives, as the name suggests, end in “i.” You may already be able to conjugate the present tense of an i-adjective, which would look like this:

• It is scary.
  • Kowai.
    • こわい。

• It is not scary.
  • Kowakunai.
    • こわくない。

If you can conjugate adjectives in the present tense, you can do it in the past too! Take the “i” off of the i-adjective and replace it with:

Positive form: katta

Negative form: kunakatta

In other words:

• Past positive form: It was scary.
  • Kowakatta.
    • こわかった。

• Past negative form: It was not scary.
  • Kowakunakatta.
    • こわくなかった。

Now you know everything you need to know in order to conjugate every single i-adjective in existence to the past tense!

Remember that when you’re speaking in the past tense and using an i-adjective, you do not conjugate the verb “to be” to the past tense, like you would in English!

In fact, to make all of these statements formal, you only need to add です at the end of the sentence, no matter whether it’s past or present, positive or negative, always add です and that’s it!

• It is scary. (formal)
  • Kowai desu.
    • こわいです。
• It was not scary. (formal)
  • Kowakunakatta desu.
    • こわくなかったです。

Na-Adjectives

Na-adjectives are the other type of adjectives used in Japanese. And here’s the good news—because na-adjectives use desu, you already know how to conjugate these!

As a bit of a refresher:

• It’s important.
  • Taisetsu desu.
    • 大切です。

• It’s not important.
  • Taisetsu dewa arimasen.
    • 大切ではありません。
• It was important.
  • Taisetsu deshita.
    • 大切でした。
• It was not important.
  • Taisetsu dewa arimasen deshita.
    • 大切ではありませんでした。

As you can see, much of Japanese plays upon itself, and once you begin to learn things, you can likely use that knowledge elsewhere to dramatically expand what you’re able to speak, write, and read! 

Moving Into More Advanced Conjugation

Japanese is a large network of interlaced parts. If you can learn some basic conjugations, soon the whole world opens up to you as your knowledge builds upon itself and grows. The past tense of Japanese verbs is no exception.

And in case you were wondering, learning the Japanese past tense sets you up well to begin mastering more casual Japanese, as well as other conjugations, like saying that you're doing something over a period of time.

The more you learn, the more what you learn in the future will make sense!

It’s important that you don’t just stick to reading guides about Japanese, though. They’re a great place to start, but nothing can replace actively engaging with the culture and its people.

Whether it’s finding a pen pal, reading Japanese books, or simply watching a Japanese movie with subtitles, be sure that you’re exposing yourself to as much native Japanese as possible.

This immersion is critical to the long-term foundation of Japanese as a language you have developed mastery in. Try picking out your favourite Japanese-related task and making a note of every time someone uses the past tense!

Just like a muscle, you’d better get that brain some exercise!