"This boy needs to sleep more."

Translation: Этому мальчику надо спать больше.

[pheonican]

The difference between "надо" and "нужно"? Are they just interchangeable or used depending on the situation?

[mosfet07]

"на́до" is more colloquial

[Theron126]

Also надо can only be used with a verb, I believe. If you're saying that you need an object, you have to use нужно, correct?

Edit: of course нужно has to agree in gender with the object in question in that case.

[mosfet07]

"на́до" is from "на́добность (в чём-то)" (one needs smth.) or "надлежи́т (сделать что-то)" (it is necessary to do smth.)
"ну́жно" is from "нужда́ (в чём-то)" (need of, necessity)

It seems, you're right, "на́до" cannot be used with nouns:

• Мне надо (нужно) быть дома (I need to be at home)
• Мне надо (нужно), чтобы ты был дома (I need you to be at home)

but "ну́жно" can be:

• Мне нужен этот стол (I need this table)
• Мне нужно это яблоко (I need this apple)
• Мне нужна эта кошка (I need this this cat)

You can't say "Мне надо яблоко", it sounds childish.

But sometimes you will hear incomplete sentences in which the verb is implied:

• Мне надо домой / Мне надо ехать домой (I have to go home)
• Если надо - сделаю / Если надо это сделать, то я это сделаю (If it is required to do, I will do it)
• In the market: Что вам нужно? -- Мне надо (купить) 10 яблок (What do you want? -- I need ten apples) [very colloquial]

Also "на́до" is used in a large number of untranslatable set expressions, questions, answers and exclamations:

• Надо так надо (If you must, you must)
• Так тебе и надо (You deserve it)
• Надо? Не надо. (Do you need this? No, I don't)
• Не надо так! (Don't do this!)
• Он парень что надо (He is a great guy)
• Надо бы... (It should be)
• ... and many more

---

In short:

• "ну́жно" indicates the need for something.
• "ну́жно" and "на́до" (colloquial) is about the need to do something.

[Theron126]

Great answer. Thanks!

[Pierre639683]

Why is it этому мальчику and not это мальчик ? It seemed to me that это мальчик was the nominative singular form. What am i missing ?

[AlexanderB462517]

это мальчик is nominative, like you said; but when using need (нужно или надо) the thing that needs it becomes dative. I know this post is two years old, but someone else may have the same question reading now :)

[avernie]

You're a saint. That was exactly the case :)

[edrec]

What's wrong with "Этот мальчик должен больше спать"?

[lunaexoriens]

Would "Этой мальчик нужен болше спать" work?

[R_Andersson]

побольше, or is that only used as the comparative degree of большой?

[mlocice]

why can't I say более?

[Cyber-Yellow]

I read that надо cannot be used with nouns. But then there is this famous line: Что вам надо? Шоколада! Could somebody explain why надо is used in this case?

[ArSa69]

So много is completely out uh...?

[Languagecr10]

I think that's because много means "a lot", больше means more

[jamiedoeslangs]

would you use "поспать" here if the boy woke up too early today and needs more sleep, or still спать?

[Zuzanetka]

Этот мальчик должен спать больше. Not accepted. WHY?

[RosalineLa2]

At last I see the value of this app! Thank you, Eugene! I hadn't realised how very useful the commentary /Q&A section is. Сейчас я знаю. Спасибо.

[Claudio_IT]

Why is "этому мальчику надо спать побольше" marked wrong? It is a construction similar to those of the previous chapter, when побольше was always used for clothes. Thank you

[AntonioMar149195]

I agree with you, I live in Kazakhstan and I often hear надо побольше спать

[AntonioMar149195]

Why этому мальчику надо побольше спать is not correct?

[Jay239607]

Why "этот мальчик нужен больше спать" is not acceptable?

[Stefan_Hey]

How about: “ этот мальчик должен спать больше”

[CrixBuddy]

Why not "нужен"? Мальчику is Masculine noun.