How to Say “I Did” in Japanese: ～ました (Mashita)

Your Japanese teacher asks what you did yesterday. You know how to say "I eat" and "I study," but how do you change those sentences to talk about something you've already done?

The short answer

Change the polite verb ending ます (masu) to ました (mashita) to talk about a completed action in the past.

For example, たべます (tabemasu, "eat") becomes たべました (tabemashita, "ate").

That's a complete Japanese sentence about something you did yesterday.

Let's learn how to build more.

Change ます to ました

Many beginner Japanese verbs use the polite ending ます (masu).

To make these verbs past tense, replace ます with ました (mashita).

Start with たべます (tabemasu, "eat").

1. たべますTabemasu.I eat.
2. たべましたTabemashita.I ate.

Notice that the beginning of the verb stays the same.

Only the ending changes.

You can apply this to other polite verbs you've already learned.

1. のみますNomimasu.I drink.
2. のみましたNomimashita.I drank.
3. みますMimasu.I watch.
4. みましたMimashita.I watched.

The pattern is consistent:

ます → ました

You don't need to memorize an entirely new verb for each past action.

Once you know the polite ます form, you can use this change to make its polite past form.

Use きのう to talk about yesterday

Now imagine you're telling a friend about your day.

You want to say that you drank water yesterday.

The Japanese word for "yesterday" is きのう (kinou).

Place it near the beginning of your sentence.

Here's what each part contributes.

きのう (kinou) tells us when the action happened.

みず (mizu) means "water."

を (o) marks what you drank.

のみました (nomimashita) tells us that the drinking happened in the past.

You can replace the drink with something else.

Notice that the verb stays at the end.

Japanese often places the action at the end of a sentence, even when you add information about when something happened.

If you need a refresher, see Basic Japanese Sentence Order.

Talk about what you studied yesterday

You can also use ～ました to describe activities.

For example, べんきょうします (benkyou shimasu) means "study."

Its polite past form is べんきょうしました (benkyou shimashita).

Imagine your teacher asks what you studied yesterday.

You could answer:

You can use the same pattern with other subjects.

The subject you're studying changes, but the verb stays the same.

You can also describe other past activities.

For example:

Now you can talk about studying, eating, drinking, and watching something in the past.

Switch back to ます when talking about tomorrow

There's an important difference between saying what you did yesterday and what you'll do tomorrow.

Japanese uses the same polite non-past form for present and future actions.

For example, べんきょうします (benkyou shimasu) can mean "I study" or "I'll study," depending on the situation.

Compare these sentences:

1. きのう、にほんごをべんきょうしましたKinou, nihongo o benkyou shimashita.I studied Japanese yesterday.
2. あした、にほんごをべんきょうしますAshita, nihongo o benkyou shimasu.I'll study Japanese tomorrow.

The word あした (ashita) means "tomorrow."

Notice the two changes.

Yesterday uses きのう (kinou) and the past ending ました (mashita).

Tomorrow uses あした (ashita) and the non-past ending ます (masu).

This is why you shouldn't automatically translate ます as "present tense."

It can describe future actions too.

Use ました for a past event, not just an experience

Imagine you're talking about a trip to Japan.

There are two different things you might want to communicate.

You could tell someone that you went to Japan last year.

Or you could tell them that you've visited Japan at some point in your life.

These aren't quite the same.

To describe a particular past event, use ～ました.

Here, きょねん (kyonen) means "last year."

You're describing a trip that happened at a particular time.

But if you want to say you've had the experience of visiting Japan, you can use another pattern:

The second sentence focuses on whether you've had that experience, rather than describing when a particular trip happened.

You can learn that distinction in How to Say “I Have Done It Before” in Japanese.

For today's lesson, focus on using ～ました to describe past actions.

Common mistakes

• Adding ました after ます instead of replacing it. To say "ate," use たべました (tabemashita), not たべますました. Remove ます before adding ました.
• Using ます for an action that happened yesterday. If you're describing something you completed yesterday, use the past form. For example, きのう、すしをたべました (kinou, sushi o tabemashita) means "I ate sushi yesterday."
• Thinking ました automatically means "yesterday." The ending tells you that an action happened in the past, but it doesn't specify when. Add きのう (kinou, "yesterday") or きょねん (kyonen, "last year") when that information matters.

Practise ～ました

Imagine you're telling your Japanese teacher what you did yesterday.

Start by saying that you studied Japanese.

Now describe two more activities.

Say that you drank coffee yesterday, then say that you watched a movie yesterday.

Use these verbs:

のみました (nomimashita, "drank")

みました (mimashita, "watched")

Try saying each sentence aloud without looking at the earlier examples.

Next, practise changing the time.

Say that you'll study Japanese tomorrow.

Finally, think about something you actually did yesterday.

Can you describe it using a verb you already know?

Start with a familiar action, such as eating, drinking, studying, or watching something.

The goal is to get comfortable switching between ます and ました when the time changes.

Keep this in mind

To describe a past action politely, change the verb ending ます (masu) to ました (mashita). Add a time word such as きのう (kinou, "yesterday") when you want to say when it happened. Once you know this pattern, you can turn many familiar Japanese verbs into sentences about what you've already done.