Lesson 20
1. Top
2. Kanji in Lesson 20
3. たんご
4. 会話
5. ぶんぽう
1. Transitive/Intransitive V
2. Vてしまう: V completely
3. S1と、S2: If/When(ever)
4. V1ながら、V2 (While V1)
5. …ばよかった (I wish)
6. れんしゅう
1

Transitive and Intransitive Verbs

Japanese often uses different verbs depending on whether the speaker describes someone doing something to an object or something undergoing a change. A transitive verb describes an action directed toward something. The person who performs the action may or may not be explicitly mentioned, but the thing affected by the action is typically marked by を.
  • ドアをあける。 (Someone) opens the door.
  • 電気(でんき)をつける。 (Someone) turns on the light.
  • お湯(ゆ)をわかす。 (Someone) boils water.
An intransitive verb, by contrast, describes what happens to or changes with the thing itself, without presenting someone as acting on it. The thing that undergoes the change is typically marked by が.
  • ドアがあく。 The door opens.
  • 電気がつく。 The light comes on.
  • お湯がわく。 The water comes to a boil.
English often uses the same verb for both meanings (Someone opens the door / The door opens). Japanese, however, frequently uses two different verbs. These are called a transitive–intransitive pair.
Transitive: someone does something
Intransitive: something happens/changes
ドアを あける。(る-V)
Someone opens the door.
ドアが あく。(う-V)
The door opens (by itself).
ドアを しめる。(る-V)
Someone closes the door.
ドアが しまる。(う-V)
The door closes (by itself).
電気を つける。(る-V)
Someone turns on the light.
電気が つく。(う-V)
The light comes on.
電気を けす。(う-V)
Someone turns off the light.
電気が きえる。(る-V)
The light goes off.
コンピュータを こわす。(う-V)
Someone breaks the computer.
コンピュータが こわれる。(る-V)
The computer breaks/goes out of order.
子どもを おこす。(う-V)
Someone wakes up children.
子どもが おきる。(る-V)
Children wake up.
おゆを わかす。(う-V)
Someone boils water.
おゆが わく。(う-V)
Water boils.
コップを おとす。(う-V)
Someone drops a glass.
コップが おちる。(る-V)
A glass drops.
Xに 水を いれる。(る-V)
Someone puts water into X.
Xに 水が はいる。(う-V)
Water is put into X.
水を だす。(う-V)
Someone turns on water.
りょうりを だす。
Someone serves/brings out a meal.
水が でる。(る-V)
Water comes out.
りょうり
が でる。
A meal is served/brought out.
へやを よごす。(う-V)
Someone makes the room dirty.
へやが よごれる。(る-V)
The room becomes dirty.
ちゅうもんを きめる。(る-V)
Someone decides on the order.
ちゅうもんが きまる。(う-V)
The order is decided on.
かぎを かける。(る-V)
Someone locks (something).
時間を かける。
Someone takes time.
お金を かける。
Someone spends money.
電話を かける。
Someone makes a phone call.
かぎが かかる。(う-V)
(Something) becomes locked.
時間が かかる。
(Something) takes time.
お金が かかる。
(Something) costs money.
電話が かかる。
Phone rings.

車を とめる。(る-V)
Someone stops the car.

水をとめる。(う-V)
Someone stops water.

車が とまる。(う-V)
The car stops.
水が とまる。(る-V)
Water stops (coming out).
びょうきを なおす。(う-V)
Someone cures an illness.
テレビを なおす。(う-V)
Someone repairs the TV.
びょうきが なおる。(う-V)
The illness is cured.
テレビが なおる。(う-V)
The TV is repaired.
ごはんを のこす。(う-V)
Someone leaves/retains some food.
ごはんが のこる。(う-V)
Some food remains.
ごみを かたづける。(る-V)
Someone puts away trash.
ごみが かたづく。(う-V)
Trash is put away.
おきゃくを のせる。(る-V)
Someone loads passengers.
おきゃくが のる。(う-V)
Passengers get on.
おきゃくを おろす。(う-V)
Someone drops off passengers.
おきゃくが おりる。(る-V)
Passengers get off (the train, etc.).
メッセージを まわす。(う-V)
Someone forwards the message.
メッセージが まわる。(う-V)
The message is forwarded.
れんしゅうを つづける。(る-V)
Someone continues the practice.
れんしゅうが つづく。(う-V)
The practice continues.
These pairs illustrate an important difference in perspective:
  • 私がコップをおとしました。 I dropped the glass. → focuses on what I did
  • コップがおちました。 The glass fell. → focuses on what happened to the glass

The intransitive sentence does not necessarily mean that the event happened by itself or that nobody caused it. It simply does not present the person or thing responsible for causing the event. This difference becomes especially important in conversation, where speakers may choose a transitive or intransitive verb depending on what they want to emphasize.

⚠Not all Japanese verbs have a corresponding transitive or intransitive partner. When a pair does exist, however, it is useful to learn the two verbs together.

Some Useful Patterns

  1. A verb ending in …す is often transitive.

    わく → わかす

    おきる → おこす

    なおる → なおす

    でる → だす

  2. In many pairs, the transitive verb ends in …える.

    あく → あける

    しまる → しめる

    つく → つける

    きまる → きめる

These are only rules of thumb, however. They do not work for every pair, so you should not use the form alone to decide whether an unfamiliar verb is transitive or intransitive.

Transitive and Intransitive Verbs with …ている

The contrast becomes especially noticeable with …ている. With many transitive verbs, …ている describes an action that is currently in progress:
  • ドアをあけています。  (Someone) is opening the door.
  • おゆをわかしています。  (Someone) is boiling water.
With many intransitive verbs that express a change, …ている describes the state resulting from that change:
  • ドアがあいています。  The door is open.
  • 電気がきえています。  The light is off.
  • おゆがわいています。  The water has come to a boil / The water is boiling hot.
In casual speech, the い in …ている and …ていない is often omitted:
  • あいている → あいてる
  • ついていない → ついてない

Transitive and Intransitive Verbs in Conversation

Choosing between a transitive and an intransitive verb is not simply a matter of describing whether someone caused an event. The choice also reflects the speaker's perspective. A transitive verb focuses on someone's action on something, while an intransitive verb focuses on what happens to something or what state it is in. The following conversations illustrate how speakers naturally switch between the two perspectives.

Conversation 1: Is the TV on?

A is asking about the current state of B's TV.
  • A: テレビはついていますか。 Is the TV on?
  • B: いいえ、ついていません。つけましょうか。 No, it isn't. Shall I turn it on?
  • A: ええ、つけてください。 Yes, please turn it on. (B pushes the TV button.)
  • B: つきませんね。こわれているみたいです。 It won't come on. It seems to be broken.
Notice how the conversation switches between つく (intransitive) and つける (transitive). ついている/ついていない describes the state of the TV: it is on or off. When B offers to do something to change that state, B uses the transitive つける: “Shall I turn it on?” After pressing the button, however, B says つきません: “It won't come on.” The focus is now on what is—or, in this case, is not—happening to the TV.

Conversation 2: Cleaning up

A has asked B to help clean up the house.
  • A: おさらはかたづいている?  Are the plates put away?
  • B: かたづいてないよ。  No, they're not.
  • A: じゃ、かたづけて。  Then, put them away.
  • B: はい。 (B drops a plate.)   カーペットをよごしてごめんなさい。  Sorry I got the carpet dirty.
  • A: ふくもよごれちゃったね。  Your clothes got dirty, too.
Again, the verb choice changes with the speaker's perspective. かたづいている describes the current state of the plates, while かたづける describes the action A wants B to perform.
The last two lines provide another useful contrast. B says カーペットをよごしてごめんなさい, using the transitive よごす, because B is apologizing for what B did to the carpet, even though it was accidental. A then uses the intransitive よごれる in ふくもよごれちゃったね, focusing instead on what happened to B's clothes. This illustrates an important point: transitive does not necessarily mean intentional. Someone can accidentally drop, break, or dirty something and still use a transitive verb:
  • コップをおとしちゃった。  I accidentally dropped the glass.
  • カーペットをよごしちゃった。  I accidentally got the carpet dirty.

Conversation 3: What happened to the pizza?

A asks B if it is okay to eat some pizza.
  • A: このピザ、食べてもいい?  Can I have some of this pizza?
  • B: いいけど、少しのこしといて。  Sure, but leave some for me. (Later)
  • B: ピザがのこってない!  There's no pizza left!
  • A: あれ? テーブルにおいといたよ。 Huh? I left it on the table.
     いぬが食べちゃったのかな?  I wonder if the dog ate it.
B first uses the transitive のこす to request an action: 少しのこしといて “Leave some.” Later, B discovers an unexpected state and uses the intransitive のこる: ピザがのこってない! “There's none left!” The intransitive expression focuses on the unexpected situation B discovers, without saying who is responsible for it.
2

Vてしまう: Completion and Unintended/Regrettable Outcomes

The pattern Vて + しまう has two closely related uses:
  • Completion: an action is carried out completely or to the end.
  • Unintended or regrettable outcome: something happens unintentionally, unexpectedly, or contrary to what the speaker wanted.

The exact meaning depends largely on the verb and the context.

1. Completion: “completely,” “all the way,” “finish V-ing”

With an action that can naturally be completed, Vてしまう emphasizes that the action is carried through to completion. Depending on the context, English may use completely, all, finish, or up, although often there is no direct English equivalent.
  • そのケーキを全部食べてしまいました。 I ate the whole cake. / I finished the cake.
  • この本はもう読んでしまいました。 I've already finished reading this book.
  • 宿題をしてしまったから、今晩(こんばん)わ あそべます。 I've finished my homework, so I can have fun tonight.
In these examples, the speaker is simply emphasizing that the action has been completed. There does not have to be any feeling of regret.

2. Unintended or Regrettable Outcome: “unfortunately,” “accidentally,” “end up V-ing”

Vてしまう can also indicate that something happened unintentionally or that the result is unfortunate or contrary to the speaker's wishes. English often expresses this meaning with accidentally, unfortunately, or end up, although these words do not always need to appear in the translation.
  • きょうは日本語のクラスがあったけど、休んでしまいました。 I had Japanese class today, but I ended up missing it.
  • 友だちからかりたコンピュータを こわしてしまいました。 I accidentally broke the computer I borrowed from my friend.
  • さいふを電車に わすれてしまいました。 I left my wallet on the train.

With verbs such as こわす “break,” わすれる “forget,” and なくす “lose,” the context often makes it natural to interpret …てしまう as expressing an unwanted or regrettable result.

Sometimes Both Meanings Are Possible

The two meanings are not always completely separate. An action can be completed and, at the same time, be something the speaker regrets.
  • そのケーキを全部食べてしまいました。 I ate the whole cake.
This sentence tells us that the cake was completely eaten. Depending on the situation and the speaker's tone, it may simply describe completion, or it may suggest something like: I ended up eating the whole cake (even though I hadn't intended to). Therefore, it is usually better to determine the meaning of …てしまう from the context rather than assume that the form itself always expresses regret.

Events Outside the Speaker's Control

When …てしまう describes an event that the speaker cannot control, the completion meaning is usually not the main point. Instead, it often indicates that the event has produced an unfortunate or undesirable result.
  • きょうはピクニックに行くつもりだったけど、雨がふってしまいました。 I intended to go on a picnic today, but unfortunately it rained.
  • 勉強(べんきょう) していたら、電気が きえてしまいました。 While I was studying, the lights went out.
  • 友だちからかりたコンピュータが こわれてしまいました。 The computer I borrowed from my friend broke.
Compare the last two examples:
  • 友だちからかりたコンピュータを こわしてしまいました。 I accidentally broke the computer I borrowed from my friend.
  • 友だちからかりたコンピュータが こわれてしまいました。 The computer I borrowed from my friend broke.
The first uses the transitive verb こわす, so the speaker is presented as the person who caused the computer to break. The second uses the intransitive verb こわれる, so the sentence simply describes what happened to the computer.

Casual Contractions: …ちゃう/…じゃう

In casual conversation, …てしまう is very commonly contracted to …ちゃう. After the で-form, …でしまう becomes …じゃう.
  • テレビを見てしまう。 → テレビを見ちゃう。
  • さとうをつかってしまいました。 → さとうをつかっちゃいました。
  • コーラを飲んでしまった。 → コーラを飲んじゃった。
  • その本を読んでしまいます。 → その本を読んじゃいます。

Thus:

  • Vてしまう → Vちゃう
  • Vでしまう → Vじゃう

The contracted forms are especially common in everyday speech, while the full forms …てしまう/…でしまう are more appropriate in formal speech and writing.

3

S1と、S2: If/When(ever) S1, S2

In Lesson 18, we learned the pattern S1と、いいです (“I hope S1”). This pattern is related to the more general S1と、S2 construction introduced here. In S1と、S2, S1 presents a condition, and S2 describes what regularly, automatically, predictably, or naturally follows when that condition is met. Depending on the context, と can be translated as “if,” “when,” or “whenever.”
S1と、(Condition)
S2 (Result)  
このボタンをおすと、 電気がつきます。 If you push this button,
the light comes on.
べんきょうしないと、 せいせきがわるくなる。 If you don't study, your grade will get worse.
春(はる)になると、 あたたかくなります。 When spring comes, it gets warm.

Regular or Repeated Events

S1と、S2 is commonly used for natural phenomena, mechanical operations, general tendencies, and habitual or repeated events. In these cases, it often means “whenever S1 happens, S2 happens.”

  • 春(はる)になると、あたたかくなります。 When spring comes, it gets warm.
  • ねないと、病気(びょうき)になりますよ。 If you don't get enough sleep, you'll get sick.
  • このボタンをおすと、ドアがあきます。 If you push this button, the door opens.
  • 子どものとき、公園(こうえん)に行くと、よくいぬとあそびました。 When I was a child, whenever I went to the park, I often played with a dog.
Notice that S2 does not have to describe something beyond a person's control when the sentence describes a habitual or repeated event. In the last example, playing with the dog was an intentional action, but it was something that regularly happened when the speaker went to the park.

Discovering Something after S1

S1と、S2 can also describe a one-time past event in which S2 is what the speaker experienced, noticed, or discovered after S1 occurred.
  • 家に帰ると、てがみが来ていました。 When I got home, I found that a letter had arrived.
  • ドアをあけると、ねこがいました。 When I opened the door, there was a cat.
  • 外に出ると、雨がふっていました。 When I went outside, I found that it was raining.
This use of と is especially common in narratives. S1 moves the situation forward, and S2 presents what happened or what was discovered next. English often translates this use simply as “when” or “upon V-ing.”

Grammatical Constraints

There are several important restrictions on the S1と、S2 pattern.

1. S1 must be in the non-past form.

The predicate before と is normally in the non-past plain form, even when the entire sentence describes a past event.
  • 〇 まどをあけると、部屋が寒(さむ)くなりました。  When I opened the window, the room became cold.
  • ✽ まどをあけたと、部屋が寒くなりました。 [Ungrammatical]

The second sentence is ungrammatical because と does not follow the past form あけた in this conditional pattern.

2. S1 must occur before S2.

S1 establishes the condition or event after which S2 follows.
  • このボタンをおすと、電気がつきます。 If you push this button, the light comes on.
However:
  • ✽ あした学校に行くと、バスで行きます。 [Ungrammatical]  When I go to school tomorrow, I will go by bus.
Here, “going to school” and “going by bus” are not naturally interpreted as two successive events. To express “when doing S1”, use 時(とき):
  • あした学校に行く時、バスで行きます。 When I go to school tomorrow, I'll go by bus.

3. S2 normally cannot express speaker's volitional actions

S2 normally cannot express the speaker's volitional actions such as request, command, invitation, intention, desire, suggestion, or other decision about what to do. Because と presents S2 as something that follows from S1 rather than as a decision to be made after S1, expressions such as the following normally do not occur in S2:
  • Vてください — request
  • Vなさい — command
  • Vましょう — invitation/volition
  • Vたい — desire
  • Vつもりです — intention
  • Vたほうがいい — advice
For such meanings, …たら is normally used instead.
  • ✽ メロンがあると、買ってきてください。 [Ungrammatical]
  •  メロンがあったら、買ってきてください。  If they have melons, please buy one.
  • ✽ そつぎょうすると、日本ではたらきたいです。 [Ungrammatical]
  •  そつぎょうしたら、日本ではたらきたいです。  When I graduate, I want to work in Japan.
  • ✽ 日本に行くと、京都(きょうと)にも行きましょう。 [Ungrammatical]
  •  日本に行ったら、京都にも行きましょう。  When we go to Japan, let's go to Kyoto, too.

One-Time Past Events and Intentional Actions

With a one-time past event, と often introduces something that happened or was discovered immediately afterward:
  • 家に帰ると、母がリビングにいました。 When I got home, my mother was in the living room.
  • 家に帰ると、電話がなりました。 When I got home, the phone rang.
However, と can also be followed by an intentional action in a past narrative:
  • 家に帰ると、母に電話しました。 When I got home, I called my mother.
This is possible, especially in written or narrative Japanese, and can have the sense of “Upon arriving home, I called my mother.” This is a so-called "story-telling mode" of と. In ordinary conversation, however, if the speaker simply wants to say that one intentional action was performed after another, …たら or …てから is often more natural:
  • 家に帰ったら、母に電話しました。 When I got home, I called my mother.
  • 家に帰ってから、母に電話しました。 After I got home, I called my mother.

と vs. たら

Both と and たら can express a condition, but they have different tendencies. …と presents S2 as a regular, predictable, automatic, or naturally following result of S1.

  • このボタンをおすと、ドアがあきます。 If you push this button, the door opens.

…たら is more flexible. It can be used when S2 expresses a request, command, intention, desire, suggestion, or decision.
  • 駅(えき)についたら、電話してください。 When you get to the station, please call me.
  • 日本に行ったら、京都(きょうと)にも行きたいです。 When I go to Japan, I want to go to Kyoto, too.
Another difference can be seen in technical and scientific writing. Because …と presents S2 as the objective result that follows when the condition in S1 is met, it is well suited for the matter-of-fact description of procedures, observations, and cause-and-effect relationships often found in scientific and technical writing.
  • 温度(おんど)を上げると、圧力(あつりょく)が高くなる。 When the temperature is increased, the pressure rises.
  • スイッチを入れると、装置(そうち)が作動(さどう)する。 When the switch is turned on, the device begins to operate.
In such descriptions, the writer is not presenting S2 as a personal decision or intention. Rather, S2 is presented objectively as what occurs under the condition stated in S1. This gives …と a neutral, matter-of-fact quality that is particularly useful in explanations of how things work and in descriptions of observable results. Thus, …たら is generally more flexible in everyday conversation, while …と is especially useful for describing regular relationships, automatic results, procedures, and objective observations, as well as for narrating what happened or was discovered next.
4

V1ながら、V2 (While V1-ing)

The pattern V1ながら、V2 expresses two actions performed at the same time by the same person. It is similar to English while V-ing or while doing.... To form this pattern, take the ます-stem of V1 and add ながら.

Verb
ます-stem  + ながら
聞きます 聞き 聞きながら
食べます 食べ 食べながら
話します 話し 話しながら
します し しながら
In the V1ながら、V2 construction, V2 is the main action, while V1 describes the accompanying or background action. In Sentence 1 below, べんきょうする is presented as the main activity, and 音楽を聞く is the accompanying activity.
  Accompanying Action V1ながら Main Action V2
1. 音楽を聞きながら べんきょうする。
  While listening to music, I study.
2. けいたいで話しながら うんてんしたら、 あぶない。
  while talking on your cell phone, if you drive, it is dangerous.
3. 新聞を読みながら 食べては いけない。
  while reading a newspaper you eat is not allowed

Japanese ながら vs. English while

Be careful when translating between Japanese and English. The order of the two actions does not necessarily correspond directly.
  • 音楽を聞きながら、べんきょうする。 I study while listening to music.
Japanese places the accompanying action before ながら, while English commonly places the main action in the main clause and the accompanying action after “while.” Similarly:
  • ビールを飲みながら、サッカーを見ましょう。 Let's watch soccer while drinking beer.
Here, サッカーを見る is grammatically the main action in Japanese, and ビールを飲む is presented as the accompanying action. However, which activity is considered “main” depends on what the speaker wants to focus on. Compare:
  • 音楽を聞きながら、べんきょうする。 I study while listening to music. → studying is the main action.
  • べんきょうしながら、音楽を聞く。 I listen to music while studying. → listening to music is the main action.
Both sentences can describe essentially the same two simultaneous activities, but the speaker presents them from different perspectives.

The Subject Must Be the Same

The subject of V1 and V2 must be the same person. If two different people perform the two actions, ながら cannot be used.
  • ✽兄がテレビを見ながら、私がラジオを聞いた。 [Ungrammatical]  While my brother watched TV, I listened to the radio.
This is possible in English, but not with Japanese ながら, because 兄 is the subject of 見る while 私 is the subject of 聞く. Instead, use a construction such as … 間(あいだ) when the two actions have different subjects:
  • 兄がテレビを見ている 間(あいだ)、私はラジオを聞いた。 While my brother was watching TV, I listened to the radio.

Summary

V1ながら、V2 means that the same person performs two actions at the same time:
  • V1ます → V1ながら、V2 accompanying/background action → main action
  • テレビを見ながら、ごはんを食べる。 I eat while watching TV.
  • 歩(ある)きながら、友だちと話す。 I talk with my friend while walking.
  • コーヒーを飲みながら、本を読む。 I read a book while drinking coffee.
5

…ば、よかった: I wish/I should have

We have already seen two conditional forms: S1たら、S2 and S1と、S2. Another conditional form is …ば. In this lesson, we first use the ば-form in the pattern …ばよかったです. Literally, this means “If X had happened, it would have been better.” It is used when the speaker looks back at a past situation and thinks that a different action or outcome would have been better. Because the desired situation did not actually happen, this pattern often expresses regret. Depending on the sentence, it can be translated as “I wish...” or “I should have....”

S1 ば、 (Condition) S2 (Result)
もっとべんきょうすれば、 よかったです。 I wish I had studied more.
はやく家に帰れば、 よかったです。 I should have gone home earlier.
雨がふらなければ、 よかったです。 I wish it hadn't rained.

…ばよかった: “I should have...”

When the speaker regrets not doing something, use an affirmative verb before …ばよかった:
  • もっとべんきょうすればよかったです。 I wish I had studied more.
  • 先生に聞けばよかったです。 I should have asked the teacher.
In each case, the action before ば did not actually happen:
  • もっとべんきょうすればよかった。 → I didn't study enough, and now I regret it.

…なければよかった: I wish ... hadn't/I shouldn't have...

When the speaker regrets something that did happen, use the negative form …なければよかった:
  • あんなことを言わなければよかったです。 I wish I hadn't said something like that. I shouldn't have said that.
  • ケーキを全部食べなければよかったです。 I wish I hadn't eaten the whole cake.
  • 雨がふらなければよかったです。 I wish it hadn't rained.
Again, the actual situation is the opposite:
  • あんなことを言わなければよかった。 → I said it, and now I regret it.
  • 雨がふらなければよかった。 → It rained, and I wish it hadn't.
Thus, …ばよかった describes a counterfactual situation: the speaker imagines an alternative to what actually happened and says that the alternative would have been better.

How to Form the ば-Conditional

The ば-conditional is formed as follows.
Type Plain Form Rule: Change... ば-Form
い-adjective おもしろい
final い to ければ おもしろければ
Negative ない い to ければ なければ
な-adjective Noun べんりだ
雨だ
だ to なら(ば) べんりなら(ば)✅ 雨なら(ば)✅
る-verb みる
おきる
る to れば みれば
おきれば
る-verb つかう
あく
はなす
まつ
よむ
かえる
final /-u/ to /-eba/
つかえば
あけば
はなせば
まてば
よめば
かえれば
Irregularverb する
くる
  すれば
くれば
For う-verbs, you can think of the change as moving the final kana to the corresponding え-row kana and adding ば:
  • う → えば
  • く → けば
  • ぐ → げば
  • す → せば
  • つ → てば
  • ぬ → ねば
  • ぶ → べば
  • む → めば
  • る → れば

For example:

  • 書く → 書けば
  • 話す → 話せば
  • 待(ま)つ → 待てば
  • 読む → 読めば
  • 帰る → 帰れば

✅ なら and ならば

For nouns and な-adjectives, the ば-conditional uses ならば:
  • 学生だ → 学生ならば
  • しずかだ → しずかならば
In modern Japanese, the final ば is very often omitted:
  • 学生ならば → 学生なら
  • しずかならば → しずかなら
Thus, the なら conditional learned earlier is historically and grammatically related to the longer form ならば.

Casual Contraction: …きゃ

In casual speech, …ければ can be contracted to …きゃ:
  • 行かなければ → 行かなきゃ
  • はやければ → はやきゃ

In the phrase Vなければいけない ("must V"), the いけない ending itself can also be omitted in casual speech. This results in a short phrase:

  • べんきょうしなければいけない → べんきょうしなきゃ: I've got to study.

…ばいい: “I hope...”

If よかったです is changed to いいです, the reference is no longer to a regretted past situation. …ばいいです can express the speaker's hope that a desirable situation will occur.
  • あした雨がふらなければいいです。 I hope it won't rain tomorrow.
  • テストがやさしければいいですね。 I hope the exam is easy.
A similar hope can also be expressed with the conditional patterns learned earlier.
  • 雨がふらなければいいです。 I hope it won't rain.
  • 雨がふらないといいです。 I hope it won't rain.
  • 雨がふらなかったらいいです。 I hope it won't rain.
Of these, …といい and …ばいい are especially common for expressing hopes. The important contrast in this lesson is:
  • …ばいい → a desirable situation 雨がふらなければいい。 I hope it doesn't rain.
  • …ばよかった → a desirable situation that did not occur 雨がふらなければよかった。 I wish it hadn't rained.

 

L20-Grammar