JLPT N4 Grammar – Difference between “〜たらいい” and “〜たらどう”
Table of Contents
1. Difference between “〜たらいい” and “〜たらどう”
2. ～たらいい
3. ～たらどう
4. Let’s Compare
5. Summary
6. Quiz
7. Similer Articles
8. Comments
Q: What is the difference between “〜たらいい” and “〜たらどう”?
A: “〜たらいい” is used when the speaker asks the listener for advice or instructions, while “〜たらどう” is used when the speaker makes a suggestion for the listener to take action.
～たらいいですか (JLPT N4)
[Meaning]
Expression used when asking for advice
[Rule]
[V] Verb た form + らいい (ですか)
[Examples]
明日は7時にそっちに行ったらいい？
Would it be good if I came over there at 7 o’clock tomorrow?
ここに名前を書いたらいいですか。
Should I write my name here?
この書類はいつまでに出したらいいでしょうか。
By when should I submit this document?
There are two main uses of ‘〜たらいい’:
・To give advice or make a suggestion to someone
・For the speaker to express their own hopes or desires”
Let’s also use this article as a reference.
On the other hand, the interrogative form “〜たらいい?” is used when asking someone for advice or instructions. The nuance changes slightly depending on how the question is asked.
There is also a range of expressions:
Polite forms: 〜たらよろしいですか / 〜たらよろしいでしょうか
① When confirming your own idea while respecting the other person’s judgment
[Example]
A：えっと、ここに名前を書いたらいいですか。
B：はい、そこにお願いします。
A: Um, should I write my name here?
B: Yes, please write it there.
⇒ The speaker is confirming with the other person whether “writing the name here” is correct.
② When asking the other person for instructions
This is used when the speaker does not know what to do and wants to leave the decision to the other person. It is often accompanied by a question word.
[Examples]
A：えっと、どこに名前を書いたらよろしいでしょうか。
B：ここに書いてください。
A: Um, where should I write my name?
B: Please write it here.
A：京都駅に行きたいんですが、何番のバスに乗ったらいいでしょうか。
B：あのバスに乗ったらいいですよ。
A: I want to go to Kyoto Station, but which bus should I take?
B: You should take that bus.
～たらどう (ですか) (JLPT N4)
[Meaning]
An expression used when suggesting to someone that they take a certain action
[Rule]
[V] Verb た form + らどう (ですか)
[Examples]
暇なら、図書館でも行って勉強したらどう？
If you’re free, why don’t you go to the library and study?
A：すみません、道に迷ってしまって。
B：この辺り、詳しくないんです。あ、あそこの交番で聞いたらどうでしょうか。
A: Excuse me, I’m lost.
B: I’m not very familiar with this area. Oh, why don’t you ask at that police box over there?
“〜たらどう” is used when making a suggestion to someone, such as “How about doing this action?”
Polite expressions: 〜たらいかがですか / 〜たらいかがでしょうか
Casual expression: 〜たら? (with “どう?” omitted)
[Examples]
母：バイトばかりして勉強してないじゃない。少し減らしたら？
Mother: You’re only working part-time and not studying. Why don’t you cut back a little?
⇒ The mother is suggesting that her child reduce the number of part-time shifts.
A：失敗するのが嫌で何もできないよ。
B：とりあえず何でもやってみたらどう？やってみないと分からないよ。
A: I’m so afraid of failing that I can’t do anything.
B: Why don’t you just try doing something first? You won’t know until you try.
上司：昨日からパソコンの調子が悪いんだよ。
部下：高田さんに聞いてみたらいかがでしょうか。彼、パソコンにとても詳しいですよ。
Boss: My computer has been acting up since yesterday.
Subordinate: Why don’t you ask Mr. Takada? He knows a lot about computers.
Let’s Compare
In the following examples, both expressions are grammatically correct, but there is a difference in nuance.
[Example]
①ここに座ったらいい？
②ここに座ったらどう？
As explained earlier, “〜たらいい？” is used when asking for advice or instructions from someone, while “〜たらどう？” is used when making a suggestion to someone.
① means “Would it be okay if I sit here?” — the speaker is asking the listener for judgment or permission regarding their own action.
② means “How about you sit here?” — the speaker is encouraging the listener to take action.
Now, in the following case, which one is correct?
[Example]
①書類のほかに他に何を用意したらいいでしょうか？
②書類のほかに他に何を用意したらどうでしょうか？
The correct answer is ①.
“〜たらいい？” can be combined with question words (such as nani “what,” itsu “when,” doko “where,” etc.).
On the other hand, “〜たらどう？” is an expression used to make a suggestion to someone, and therefore it cannot be used in a question that seeks information.
Summary
[～たらいい？]
- Basic usage: Used when asking someone for advice or instructions.
- ① Without a question word: Confirming your own idea while respecting the other person’s judgment.
- ② With a question word: When you cannot decide by yourself, you ask the other person to confirm or leave the judgment to them.
- Polite forms: “〜たらよろしいですか” / “〜たらよろしいでしょうか”
[～たらどう？]
- Basic usage: Used when the speaker makes a suggestion and encourages the listener to take action.
- Polite forms: “〜たらいかがですか” / “〜たらいかがでしょうか”
- Casual form: “〜たら？” (with “どう？” omitted)
Quiz
Read the following sentence and choose the expression that fits the context from the options provided in the parentheses.
Click on the question to check the answer.
A. 座ったらどう
大丈夫？顔色が悪いよ。ちょっとここに座ったらどう？
Are you okay? You look pale. Why don’t you sit down for a bit?
*Since the speaker is suggesting that the listener sit down because they look unwell, “〜たらどう” is correct.
A.行ったらいい
すみません、どの部屋に行ったらいい？
Excuse me, which room should I go to?
*Since the speaker is confirming which room to go to, “〜たらいい” is correct.
A. 出したらいい
レポートはいつまでに出したらいいでしょうか。
By when should I submit the report?
*Since the speaker is confirming the submission deadline, “〜たらいい” is correct.
A.聞いたら
Ａ：この問題わかる？
Ｂ：ぼくも分からないよ。あ、たかし君に聞いたら？
A: Do you understand this problem?
B: I don’t either. Oh, why don’t you ask Takashi?
*Since the speaker doesn’t know and is suggesting asking Takashi, “〜たら (どう)” is correct.
Similer Articles
- JLPT N2・N4 Grammar – The difference between ”〜にくい”, ”〜づらい” and “〜がたい”
- JLPT N4・N5 Vocabulary – The difference between “聞けない” and “聞こえない”
- JLPT N4・N5 Grammar – The difference between “〜けど” and “〜のに”
- JLPT N3・N4 Grammar – The difference between “〜ように” and “〜通りに”
- JLPT N4 Vocabulary – The difference between “何でも” and “何も”
▼ Subscribe to Our Newsletter ▼
Receive free tips for learning Japanese!
