Conditionals II

Japanese Grammar 3

Course 3 · Chapter 5 · Conditionals II: たら and なら

🔀 Conditionals (2) — たら と なら

Chapter 4 gave you と and ば. The other two conditionals are the ones you will use most. たら is the all-purpose "if / when": the main clause is unrestricted. なら picks up a topic from the conversation: "if that's the case ...". After them comes a table that decides between all four.

The rule in one box 〜たら = plain past form + ら: "if / when X has happened, then Y" (any main clause). 〜なら = plain form or noun + なら: "if (as you say / given that) X, then Y": X is a context, not a completed event. 〜たらいい = "why not ... / it would be good if".

1. たら: if or when (after X has happened)

TypeRuleExamples
Verbた-form + ら
い-adjective〜かったら
な-adjective / noun〜だったら
UseExampleEnglish
Hypothetical "if"If it rains, I won't go.
"When" (once X is done)When I arrive in Japan, I'll phone.
Request or wish in the main clauseWhen you've finished, please tell me.
Past discoveryWhen I got home, a friend was waiting.
WishIf I had money, I'd want to buy a car.

The word もし ("if, supposing") can be added to make the hypothetical clearer: もし〜たら.

たら is the safe default Unlike と (results only) and ば (conditions, mainly states), たら allows a request, wish, intention, invitation or command in the main clause, and works for both "if" and "when". If you don't know which conditional to use, たら is rarely wrong in speech.

〜たらいい / 〜たらどうですか

PatternMeaningExample
〜たらいい (ですよ)suggestion: "you could / why not"
You should go to the hospital.
〜たらどうですか"how about ...?" (a suggestion)
Why not take a little rest?
〜たらいいなあwish: "I hope / it would be nice if"
I hope summer comes soon.

2. なら: if it's the case that

なら takes what someone has just said or what is understood from the situation and builds a comment on it. It attaches to the plain form (but not the past, unless the event is completed) and to nouns and な-adjectives without だ.

TypeExamples
Verb (plain)
い-adjective
な-adjective, noun
SituationExampleEnglish
Responding to what was saidA: I'm going to Kyoto tomorrow.
B: If you're going to Kyoto, autumn is the best time.
A topic: "as for ... / if it's about ..."If it's Japanese food you want, that shop is good.
Advice about a step before doing somethingIf you're going to the sea, take a hat.
A choice or conditionIf you're free, please help.
Watch out: なら is not tied to time なら does not mean "after X is done". Compare: にほんへ いくなら、かばんを かった ほうが いい ("If you're going to Japan, buy a bag first": the buying comes before the trip) with にほんへ いったら、かばんを かいたい ("When I've gone to Japan, I'll want to buy a bag": the buying comes after). With たら the first clause is finished before the main clause; with なら the main clause often comes first or is simultaneous.

3. Choosing between と, ば, たら and なら

とばたらなら
Core meaningautomatic resultgeneral conditionif / when (after X is done)if (it's the case that)
Request / wish in main clausenoonly with state clausesyesyes
Past discoveryyesnoyesno
Attaches toplain (present)ば-formplain past + らplain (no だ)
Typicallaws, machines, directionsrules, "enough if"everyday conversationadvice, topics
A quick decision 1) Something that is always true or automatic → と. 2) Advice or a reaction to what the other person has just said → なら. 3) Anything else in conversation, especially with a request, wish or "when" → たら. 4) A general rule or "all you need is" → ば.

🗣️ In Use — つかいかた

Four conditionals in action.

① Making plans

A: What will you do if it rains tomorrow?
B: If it rains, I'll watch a film at home.

② Advice

A: I'm going to Osaka next week.
B: If you're going to Osaka, you should eat takoyaki.

③ Suggesting

A: I have a fever.
B: Why not go to the hospital soon?

📋 Quick Reference

FormRuleExample
たらplain past + らついたら; やすかったら; ひまだったら
ならplain (noun / な-adj without だ) + ならいくなら; ひまなら
〜たらいいsuggestionいったら いいですよ
〜たらどうですか"how about?"やすんだら どうですか
もし"supposing" (with たら)もし ふったら

✍️ Practice — れんしゅう

Try each one, then click to check.

1. Give the たら-form of , and .

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2. Give the たら-form of and .

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3. Say "When you've finished, please call me."

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4. Say "If I had time, I'd travel."

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5. Say "When I opened the box, it was empty." (から)

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6. Suggest "Why not ask a teacher?"

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7. A says "I'm going to Hokkaido." Reply "If you're going to Hokkaido, winter is best."

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8. Say "If you're free, let's have lunch." with なら.

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9. Which is right: or ?

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: no だ before なら.

10. Which conditional: "If you press this button, it opens"?

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: It's an automatic result.

Coming up in Chapter 6: Time Clauses. とき, まえに, あとで, あいだ, うちに, ながら, まで, たびに, the tense inside the clause, and てから revisited.