だった・でした: Polite and Casual Past Tense

Introduction

Howdy! You’re back for more already! How was your first grammar lesson? Was it epic? Why am I emphasizing “was”? Ah! So many questions, so little time!

Remember how I taught you how to form basic sentences last time? Well, today we’re going talk about how to create past tense sentences. If you think about it… this is a really indispensable skill to have in your toolkit. How else would you tell people about the amazing pepperoni and peanut butter pizza you had yesterday? What do you mean that’s a weird combination? 😕 Enough judgment and let’s get to the lesson!

It Was… Great!

Structure

• 

  Noun・な Adjectiveだった・でした
  Example:
  → 本ほんだった。
  ”It was a book.”

Just like with our だ/です pair, we will be dealing with a casual and assertive sentence ender via だった, and a more polite sentence ender: でした。

You probably noticed that these two past tense sentence-enders look very similar to their present tense companions. This is because they are in fact the same thing, just a different conjugation.

If you need a refresher, conjugation is when we alter a verb in some way to make it “agree” (i.e. work with) the rest of a sentence. Like so:

だ → だった

Still plain, casual form. Not suitable for situations where one needs to be polite. Can be assertive but is not necessarily "manly" like だ.

です → でした

Polite and non-emphatic. Suitable for a myriad of situations, including conversations with your boss and people older than you.

This may lead you to wonder if だ and です are verbs since we seem to be conjugating them! They are in fact, something called "auxiliary verbs", but we'll talk more about those once your grammar has leveled up.

Great, now let’s see some examples!

Easy peasy right? The only thing you have to be careful of is your level of politeness. More specifically, if you are in a situation where you would use です (with your boss, or someone older than you, for example), be sure to use でした when you speak in the past tense, and not だった! And the reverse is also true. Using でした instead of だった with just your pals can make you seem distant and cold.

Ugh, Those Pesky い-Adjectives and Their Rules!

Okay, I lied, there’s another thing to be careful of… Adjectives. Last time, I said that だ can’t attach to い-adjectives like 大おおきい, or おいしい, and it’s the same with だった and でした. That’s right, neither of our past tense sentence-enders can attach to い-adjectives. This is because い-adjectives have their own unique way of conjugating into the past tense. Don’t worry though, we’ll cover that!

So just remember:

• 

  い-adjective + だ ❌

• 

  い-adjective + だった ❌

• 

  い-adjective + でした ❌

Things Disappearing Into the Past…

Like I mentioned in our first lesson, when something can be inferred from context, the Japanese language loooves to omit it. This isn’t exclusive to the present tense, so let’s take a look at some past tense examples of omission.

Scenario: Bob and Peter are talking about their friend Mike.

As you can see, the Japanese sentences have no sign of “Mike”, or even “he”.

Scenario: Mike and Peter are talking about Peter's recent trip to the ocean.

Again, there’s no mention of “the water”, or “it” in the second sentence. Once the fact that we’re discussing the water has been established, in Japanese we can simply say きれいだった (literally: “pretty was”). Let’s look at one more example.

Where’d “the test” go!? Into outer space, probably. But that’s okay, it’s still perfectly comprehensible. Right?

Hopefully, you’re getting used to things disappearing from sentences, because you’re going to see this happen all the time! Anyways, congrats on making it through another grammar lesson! I can feel your power growing already…

Summary

• 

  We covered the past tense forms of だ and です: だった and でした.

• 

  だった is more casual and assertive than でした, just like its present tense counterpart, だ. Unlike だ, however, だった does not necessarily have a "manly" nuance.

• 

  Neither だった nor でした may be used with い-adjectives.

• 

  Just like with the present tense, the Japanese language likes to omit unnecessary information, so watch out!