If in Japanese: Four Forms, Two Questions, One Safe Answer

Japanese has four ways to say if: と (to), ば (ba), たら (tara), and なら (nara). The choice between them is part of the meaning.

English says if once and leaves the rest to context. Japanese doesn't. The form you pick makes a claim about the condition itself.

Each claim is different. と (to) claims the result follows by itself, every time. ば (ba) claims a general rule.

たら (tara) claims one particular occasion: this weekend, this purchase, this once. なら (nara) claims you're answering something the other person already said.

Four forms sounds like four times the homework. It isn't.

Two questions sort nearly every sentence, and the sentences they can't sort have a form waiting to catch them. That's the whole grammar: four forms, two questions, one safe answer.

One boundary before we start. The ば (ba) form is not one of the eight basic verb forms.

That grid of tense, politeness, and negation lives in the field note on verb conjugation, along with how to tell the verb groups apart. These four don't say when something happens. They say how the condition binds the result.

You need one of these four whenever your sentence has a condition, from a plan to a piece of advice. A plan, a request, or an invitation cannot follow と (to). Use たら (tara), the widest of the four, or なら (nara) when you answer something the other person already said.

A dictionary translates all four Japanese conditionals as if, so the dictionary can't tell them apart. The sentences can. Watch what happens when one first half meets two different forms — spring is the condition in both sentences below.

春になると、桜が咲きますはるになると、さくらがさきます (haruninaruto,sakuragasakimasu)

When spring comes, the cherry trees bloom.

春になったら、公園を散歩しますはるになったら、こうえんをさんぽします (haruninattara,kouenwosanposhimasu)

When spring comes, I'll take walks in the park.

Same spring, different claim. The と (to) sentence reports what the season does on its own, and the blossoms don't ask permission. The たら (tara) sentence is somebody's plan for one particular spring, and plans are exactly what と (to) refuses to host.

Here are the four claims in one view: what each Japanese conditional form claims, and what it allows in the second half of your sentence.

Ask two questions, in this order. First, does the result follow by itself, with nobody deciding anything, as with a machine, a rule, or a road? Then the form is と (to).

Second, are you building on something the other person has already said? Then it's なら (nara). When both answers are no, たら (tara) does the job, and it won't fail you.

ば (ba) sits beside the questions rather than inside them. When you're giving a general rule, ば (ba) is the form: cheaper if you wait, no charge if you spend a little more.

There is one catch about the second half, and it gets its own section below.

Try the questions on a real plan: you and a friend are watching the weather ahead of a Sunday outing. A movie doesn't follow from rain by itself, because somebody has to propose it.

And nobody has said anything to build on yet. Both answers are no, so the sentence goes to たら (tara).

日曜に雨が降ったら、映画にしませんかにちようにあめがふったら、えいがにしませんか (nichiyouniamegafuttara,eiganishimasenka)

If it rains on Sunday, shall we make it a movie instead?

That ませんか (masenka) at the end is an invitation, and invitations are fussy about which conditional they'll live under. The endings themselves — ましょう (mashou), ませんか (masenka) — have a field note of their own, on the volitional form.

と (to) is the automatic claim, and it's the simplest to build: the plain form plus と (to). It lives where results repeat without anyone's help: machines, natural laws, directions.

Press the button and the drink appears. Turn at the corner and the shop is on your right. That's と (to) country: the world doing what it does.

たら (tara) is the one-time claim. Take the plain past — the た (ta) form — and add ら (ra), so 待つまつ (matsu), to wait, becomes 待ったらまったら (mattara). The tara form covers a single, particular if, and it puts no limit on what the second half does.

These two are the pair you meet first, at N5. ば (ba) and なら (nara) arrive at N4, and the field notes on the two grammar lists show where all four sit among their neighbors.

The limit on と (to) is strict, and it's the first thing that trips people. The second half reports what happens — nothing decided, requested, or proposed gets in. Say you're seeing a friend off and you'd like a call when they arrive:

❌ 駅に着くと、電話しましょうえきにつくと、でんわしましょう (ekinitsukuto,denwashimashou)

⭕ 駅に着いたら、電話しましょうえきについたら、でんわしましょう (ekinitsuitara,denwashimashou)

Let's call is an invitation, so と (to) throws it out; たら (tara) takes it without complaint. Anything with your will in it — a plan, a request, a wish — needs たら (tara) or one of its neighbors.

And here's たら (tara) doing its plainest work. You've found something you like and you're waiting on the price tag:

安かったら、買いますやすかったら、かいます (yasukattara,kaimasu)

If it's cheap, I'll buy it.

Making the forms is the quick part — choosing is the work. Here's the one verb 待つまつ (matsu) in all four, for reference.

The Japanese ba form claims a general condition: meet it, and the result holds. A verb's final sound moves to the え (e) row and takes ば (ba) — 待つまつ (matsu) to 待てばまてば (mateba), 出るでる (deru) to 出ればでれば (dereba). An い (i)-adjective drops its い (i) for ければ (kereba), so 安いやすい (yasui) becomes 安ければやすければ (yasukereba), and negatives all use なければ (nakereba).

It's at home in rules of thumb and shop advice. Say you're checking out online and the cart is sitting a little under the free-shipping total:

あと二千円分買えば、送料は無料になりますあとにせんえんぶんかえば、そうりょうはむりょうになります (atonisen'enbunkaeba,souryouhamuryouninarimasu)

Two thousand yen more and the shipping is free.

Now the catch. ば (ba) presents the condition as the thing that settles the outcome, so the second half normally reports what happens.

It isn't the place to announce what you've decided to do. Your own plans can follow only when the first half describes a state: having time, being free, the weather being good.

State first, plan second, and everything's fine:

天気がよければ、日曜は自転車で出かけますてんきがよければ、にちようはじてんしゃででかけます (tenkigayokereba,nichiyouhajitenshadedekakemasu)

If the weather holds, I'm going out on my bike on Sunday.

Put an action in the first half, though, and requests stop fitting. Say a friend has been talking about a new bag all week:

❌ 新しいかばんを買えば、見せてくださいねあたらしいかばんをかえば、みせてくださいね (atarashiikabanwokaeba,misetekudasaine)

⭕ 新しいかばんを買ったら、見せてくださいねあたらしいかばんをかったら、みせてくださいね (atarashiikabanwokattara,misetekudasaine)

買うかう (kau) is an action, not a state, so the request can't sit after ば (ba) — たら (tara) takes it without any fuss. One spelling slip to dodge while you're here: the い (i) really does drop, so it's 安ければやすければ (yasukereba), not 安いければやすいければ (yasuikereba).

Two more uses are worth a look. ば (ba) plus よかった (yokatta) looks back at what you didn't do, as in もっと早く来ればよかったもっとはやくくればよかった (mottohayakukurebayokatta), “I should have come earlier.” That is regret, not a condition on anything.

And ばいい (baii) settles a matter and closes it, which suits directions but can sound curt to someone still deciding. A suggestion that leaves the choice open uses たらどうですか (taradoudesuka), coming up below.

なら (nara) doesn't start from nothing. It uses something the other person has already said, or a topic already raised, and builds your reply on it.

That is why advice usually takes this form. Nara is filed under the conditionals, but it behaves more like an answer.

The attachment is the simplest of the four. A plain form takes なら (nara) directly, and a noun needs nothing in between at all, as in 傘ならかさなら (kasanara).

The bare noun is where you'll hear it most, because a topic is usually a single word. Someone mentions needing an umbrella before the weekend, and the price is on their mind:

傘なら、商店街の店のほうが安いですよかさなら、しょうてんがいのみせのほうがやすいですよ (kasanara,shoutengainomisenohougayasuidesuyo)

For an umbrella, the shops in the arcade are cheaper.

Nothing about the umbrella is uncertain here. It is only the topic that was raised, taken as given, and answered. That's the なら (nara) claim, and it brings a freedom none of the other forms have: the second half may happen before the first.

One trip to a hot spring, three orders of events.

Only the なら (nara) sentence lets the buying happen before the going. You're answering a plan, so your advice points at the preparations.

The たら (tara) sentence fixes the order: first the trip, then the towel. And the last sentence is なら (nara) on a plain past, answering a trip that's already finished.

That same freedom is why advice to a traveler lands in なら (nara). A friend has told you they're off to the mountains:

山に行くなら、厚い上着を持って行ってくださいやまにいくなら、あついうわぎをもっていってください (yamaniikunara,atsuiuwagiwomotteittekudasai)

If you're heading into the mountains, take a heavy jacket with you.

What なら (nara) can't do is mark things that arrive on their own. Nobody raised ten o'clock as a topic, and the clock moves on its own:

❌ 十時になるなら、店が開きますじゅうじになるなら、みせがあきます (juujininarunara,misegaakimasu)

⭕ 十時になったら、店が開きますじゅうじになったら、みせがあきます (juujininattara,misegaakimasu)

In speech you'll also meet んなら (nnara), as in 行くんならいくんなら (ikunnara). It's the same word with んです (ndesu) folded in, and no more than a shade more casual.

たら (tara) is the widest of the four because it claims the least. One particular occasion — nothing about rules, nothing about what's been said — so there's very little a たら (tara) sentence can get wrong. That's what safe means here, and it is not a shortcut but the smallest claim of the four.

Watch it rescue a sentence the other forms refuse. A friend might drop by in the afternoon, and you'd like to go out together when they do:

❌ 友だちが来れば、一緒に出かけましょうともだちがくれば、いっしょにでかけましょう (tomodachigakureba,isshonidekakemashou)

⭕ 友だちが来たら、一緒に出かけましょうともだちがきたら、いっしょにでかけましょう (tomodachigakitara,isshonidekakemashou)

An invitation after ば (ba) needs a state in the first half, and 来るくる (kuru) is an event. So the sentence fails ば (ba) and drops neatly into たら (tara).

When a sentence breaks one form's claim, たら (tara) is usually where it ends up. That's the safety valve working.

もし (moshi) is the word English speakers go looking for, and it isn't a fifth conditional. It sits at the front of a sentence to flag that the condition is genuinely uncertain.

たら (tara), ば (ba), or なら (nara) still does the grammatical work beside it. A condition that's sure to arrive doesn't take もし (moshi), because spring comes whether you flag it or not.

Two everyday patterns are built on this same たら (tara). たらどうですか (taradoudesuka) offers advice, as in why not do it this way, and たらいいですか (taraiidesuka) asks for it, so the pair point in opposite directions.

Among friends the suggestion shrinks to たらどう (taradou). Say a colleague has been running on empty all week:

疲れているんでしょう。今週末はゆっくり休んだらどうつかれているんでしょう。こんしゅうまつはゆっくりやすんだらどう (tsukareteirundeshou.konshuumatsuhayukkuriyasundaradou)

You look worn out. How about a proper rest this weekend?

So the two questions from the top are the whole method. Does the result follow by itself? Then the form is と (to).

Are you answering what was already said? Then it's なら (nara).

A general rule with a state up front can take ば (ba). And any sentence that answers neither question already has a home: put it in たら (tara), and it holds.

Choose と (to) when the result follows by itself, and なら (nara) when you answer what was already said.

Use ば (ba) for a general rule, and put your plans after it only when the first half is a state.

When neither question decides, write たら (tara), because it claims the least.

With one of four forms, chosen by what you're claiming. と (to) marks results that follow by themselves, ば (ba) marks general rules, たら (tara) marks one particular occasion, and なら (nara) answers something already said.

Two questions pick between them: does the result follow by itself, and are you building on what was already raised? When neither settles it, たら (tara) is the safe choice.

たら (tara) claims one particular occasion and lets anything follow: plans, requests, invitations. ば (ba) claims a general condition, and its second half normally reports what happens rather than what you've decided.

Your own plans fit only when the first half is a state, like having time or the weather being good. When you're not sure, たら (tara) is the wider of the two.

When you're answering something the other person has already said, or a topic already raised. たら (tara) sets up its own condition, and なら (nara) borrows one from the conversation. なら (nara) also frees the order of events: 温泉に行くなら、タオルを買いますおんせんにいくなら、タオルをかいます (onsenniikunara,taoruwokaimasu) means you'll buy the towel before the trip, an order たら (tara) can't express.

もし (moshi) adds a note of by any chance to a conditional sentence. It isn't a conditional form itself.

It sits at the front to signal that the condition is genuinely uncertain, while たら (tara), ば (ba), or なら (nara) does the grammatical work. Conditions that are certain to happen don't take it.

たらどうですか (taradoudesuka), often shortened to たらどう (taradou) among friends, is a suggestion built on たら (tara): why don't you, how about. The mirror question たらいいですか (taraiidesuka) asks someone else what you should do, and politer company stretches it to たらいいでしょうか (taraiideshouka). Who acts on the answer is what separates them.

Ukiyoe Japanese keeps five concept lessons on the conditionals. たら (tara) and と (to) come at N5, then ば (ba) and なら (nara) at N4.

A comparison lesson is built around the same two questions you have used above, and the advice pair is built on たら (tara). Each comes backed by reviewed examples and the wrong-then-right pairs that show where a claim breaks.

The choosing itself lives in a drill on the four ifs. It gives you the first half of a sentence with the form missing — 春になるはるになる (haruninaru), blank, 桜が咲きますさくらがさきます (sakuragasakimasu) — and asks which form holds it. Miss, and the explanation walks you through the claim you broke.