How Conditionals Work in Japanese: …と, …ば, …たら, and …なら

if: ...たら

Last time, you learned how to express aims, e.g. “ほん旅行りょこうするために、ほんべんきょうしている (I’m studying Japanese to travel to Japan).” The variety of your expressions are certainly increasing now. Then, if you would like to say, “If you travel Japan, you should study Japanese,” how should it be? In this lesson, you will learn how to express conditionals.

Explanation for How to Express Conditionals in Japanese

Table of Contents
…と: Constant Results and Actual Conditions
…ば: Hypothetical Conditions
…たら: One-Time Results
…なら: Contextual Conditions
Practical Tips
Related Expressions

When it comes to expressing conditionals in English, the word: “if” has a very important role. However, Japanese has four words which are the counterpart to “if.” They are  …と, …ば, …たら, and …なら. The proper one will be determined by relations between conditional clauses and main clauses. Thus, Japanese conditionals may be more complicated than English one. Let’s tackle the usages step by step.

…と: Constant Results and Actual Conditions

はるになる さくらが(く / きます)
Condition Constant Result
If it becomes spring, cherry blossoms will come out.

The first function is to express constant results. The conjugation is just to attach the plain (dictionary) form to と. When you use nouns and na-adjectives, you need to attach だ like 春だと. By constant results, we mean that it’s an unchanged fact, e.g. one plus one is always two. You can use this for natural phenomenons, habitual actions, programmed actions, etc.

あめすずしく(なる / なります)。
If [it] rains, [it] will get cool.
なかパンを(べる / べます)。
If [I] become hungry, [I] will eat bread.
Siriシリはなしかけるへんを(する / します)。
If [I] talk to Siri, [she] will reply.
じん(モテる / モテます)。
If [you] are a beautiful woman, [you] will be popular.

The second function is to express actual conditions. This might be rather close to “and then” or “when” in English. In this context, と is often used when you introduce something that happened in the past.

新幹線しんかんせん富士ふじさんえ(た / ました)。
When [I] took the bullet train, Mt. Fuji was visible.
まつりにボブが(いた / いました)。
[I] went to the festival and then [I] found Bob (Lit. Bob was there).
質問しつもんする先生せんせいはすぐにおしえてくれ(た / ました)。
When [I] asked, the teacher taught [me] [it] right away.

This has another function which is to express sequential actions in the past. When you compare the usages between と and the te-form (sequential actions), と is more suitable to describe other people than yourself while て can describe yourself. Note: these are not conditional.

さかなって寿司すしを(つくった / つくりました)。
[I] bought fish and made Sushi.
さかなうと寿司すしを(つくった / つくりました)。
=> Unnatural!
ボブはさかなって寿司すしを(つくった / つくりました)。
=> Natural!
ボブはさかなうと寿司すしを(つくった / つくりました)。
=> Natural!

...ば: Hypothetical Conditions

Here, you have to tackle a new conjugation rule, which is called the ば-form. First, take a look at the following table to learn the conjugation. Then, learn the function that the ば-form has.

All Verbs: To Replace the last u with eba

  Plain Form ば-form
Ru-verb (miru) れば (mireba)
(kiru) れば (kireba)
U-verb (kaku) けば (kakeba)
(hanasu) せば (hanaseba)
Exception (suru) れば (sureba)
(kuru) れば (kureba)

I-adjectives: To Replace the last い with ければ

  Plain Form ば-form
I-adjectives かわい かわいければ
さむ さむければ

Na-adjectives and Nouns: To Attach であれば

  Plain Form ば-form
Na-adjective げん げんであれば
Noun じん じんであれば

Examples

台風たいふうれば 学校がっこうやすみ(だ / です)
Hypothetical Condition Result
If a typhoon has come, [our] school will be closed.

The function is to express hypothetical conditions like if a hypothesis comes true, X will happen. This indicate that you place priority on the conditional clauses rather than the main clauses.

うんよければ合格ごうかく(する / します)よ。
[You] will pass [it] if [you] are lucky.
くすりめばなおると(おもう / おもいます)。
[I] think [I] will recover if [I] take the medicine.
免許めんきょればくるまを(う / います)。
If [I] get a driver’s license, [I] will buy a car.

…たら: One-Time Results

11じゅういちなったら 出発しゅっぱつ(しよう / しましょう)
Condition One-Time Result
If it comes 11 o’clock, let’s leave.

The function is to express a one-time or a particular result. This has the widest usage and thus we can say たら is most common to express conditionals. The conjugation is to attach ら to the ta-form. By using this, you can express both actual and hypothetical conditions, e.g. 11時になる must come true and thus we define it as actual conditions.

Actual Conditions
なつたらほんに(く / きます)。
If the summer comes, [I] will go to Japan.
としったら田舎いなかに(む / みます)。
If [I] get old, [I] will live in a rural area.
Hypothetical Conditions
けんかったらくと(おもう / おもいます)。
[I] think [I] will cry if [I] pass the exam.
ほんたらさくらられ(る / ます)よ。
If [you] come to Japan, [you] can see cherry blossoms.

You can replace …たら with と when conditions are actual and …ば when conditions are hypothetical. Considering the characteristics, …と is more suitable for when results are constant and …ば is more suitable for when speakers focus on the conditional part.

 あめるとすずしく(なる / なります)
 あめったらすずしく(なる / なります)
うんよければ合格ごうかく(する / します)よ。
うんよかったら合格ごうかく(する / します)よ。

…たら often appears when you express volition, requests, invitations, etc. It’s because the results should be a one-time or a particular one. In this context, …と is not interchangeable.

かんあったら観光かんこうしたい(です)。
[I] want to go sightseeing if there is time.
よかったらつだってくれ(ない / ませんか)?
Can/could [you] help [me] if it is alright?
んだら運転うんてんするな。
If [you] drank, don’t drive [a car].
れたら公園こうえんに(かない / きませんか)?
If [it] clears up, won’t [you] go to the park?

In this context, …ば is interchangeable only when the conditional clause indicates states such as constant states and the potential form, or subjects in the conditional clause are different from ones in the main clause.

かんあったら観光かんこうしたい(です)。
[I] want to go sightseeing if there is time.
 かんあれば観光かんこうしたい(です)。
=> Natural! Because ある indicate constant states.
んだら運転うんてんするな。
If [you] drink, don’t drive [a car].
めば運転うんてんするな。
=> Wrong! Because the subject of 飲む and 運転 is the same.

…なら: Contextual Conditions

ケンがなら ぼくも(く / きます)
Condition Result
If Ken goes, I will go, too.
*Said when Ken says “I will go to the festival.”

The function is to respond to someone in a given context. Regarding the other conditional words, you can set a context by yourself. However, you can use …なら only when given a context. With the above example, Ken first said “I will go to the festival,” and then you respond to it like “If you said so…” and “if that is the case…” The conjugation is just to attach なら to the plain (dictionary) form or the ta-form, which is the only one case that you can attach conditional words to the two forms. Note: You don’t attach when you use nouns and na-adjectives.

ほんはなせるひとは(いる / いますか)?
Is there a person who can speak Japanese?
ほんならボブがはなせ(る / ます)よ。
If [you’re talking about] Japanese, Bob can speak [it].
ほんまんんでみたい(です)。
[I] want to try to read Japanese manga.
みたいならわたしのを(そう / しましょう)か?
If [you] want to read, shall [I] lend mine?

Contexts can be given not only in conversation, but also with actions. The following examples are said when you find a person who is about to leave.

かけるならかぎめて(ください)。
Please lock the door if [you] go out.
ものならたまごってきて(ください)。
Please buy eggs if [you go] shopping.

Japanese people sometimes add の or ん before なら. Especially, if you use the ta-form with なら, it will sound more natural.

ほんりょうをたくさん(つくった / つくりました)。
[I’ve] made a lot of Japanese cuisines.
たくさんつくったならわたしにもちょうだい。
If [you’ve] made a lot, please give me [some], too.
インドからして(きた / きました)。
[I’ve] moved from India.
インドからならほんさむく(ない / ありませんか)?
If [you’ve] come from India, isn’t Japan cold?

Practical Tips

You may be confused with the four ways of expressing “if.” It’s certainly not easy to properly use them in conversation. Here is a practical tip.

(1) Try to Use …たら

Firstly, please try to use …たら. This has the widest usages of the four and is interchangeable with …と and …ば. That is to say, you can make natural sentences except for when you need to use なら.

(2) Try to Use …なら If You Respond to Someone in Given a Context

Secondly, please try to use なら if …たら didn’t work well, i.e. if you respond to someone in given a context. This is the case where you cannot use …たら.

(Optional) Confirm Whether There Are More Natural Ones

If you use …たら, there may be more natural expressions. When you focus on the conditional clause, you should use …ば. When results are constant ones, you should use …と.

Related Expressions

もし: By Any Chance or If Any

もしうんよければ合格ごうかく(する / します)よ。
=> Natural!
もしかけるならかぎめて(ください)。
=> Natural!
もしあめすずしく(なる / なります)
=> Unnatural!
もしなつたらほんに(く / きます)
=> Unnatural!

もし gives a nuance of “by any chance” or “if any” to sentences. However, you cannot use it if conditional clauses indicate actual conditions because it will definitely come true.

どう(ですか)?: How about…?

さいはどう(ですか)?
How about vegetables?
さかなべるのはどう(ですか)?
How about eating fishes?

どう(ですか) is the counterpart to “How about” in English. You can express suggestions like “how about doing [it]? This is generally used when you respond to someone, e.g. “今日きょうなにべる (What will we eat today)?” “さかなはどう (how about fishes) ?”

にくべればどう(ですか)?
How about eating meats?
にくべたらどう(ですか)?
How about eating meats?

Your speech will sound advice or recommendations if you combine the conditional form: ば or たら with どうですか. Be careful; this may have a critical tone. You should use this when someone seeks your advice. Otherwise, you should use this without ば and たら.

Summary

  Constant Results Hypothetical Conditions One-Time Results Contextual Conditions
Suitable      
  Suitable    
たら Acceptable Acceptable Suitable  
なら       Suitable

We know that the length of this lesson is long. Thus, please focus on the practical tips. Firstly, please master the usage of たら and なら. After that, you can enhance your expressions to be more natural. Conditionals are one of the most frequently used expression without doubt. It’s worthwhile taking the time. Next you will learn a similar expression: Reverse Conditions.