Japanese Grammar Bank


Today we will study an essential component of the language, how to say “have to” or “must” in Japanese.

Japanese has a few ways to say “have to”, and by the end of this article you should be able to use all of them.


だめ dame
いけない ikenai
ならない naranai

Let’s start with how to express “must not” before we move onto “must”.

Add は to the て form of a verb and stick on だめ , いけない or ならない.


Verb in て form + は + だめ / いけない / ならない

For example:

食べる食べて + は + だめ=食べてはだめ
食べる食べて + は + いけない=食べてはいけない
食べる食べて + は + ならない=食べてはならない

NOTE || だめ is informal. いけない or ならない are the same level of formality, but ならない is more likely to be used for things that apply to many people at once, like rules.

View More Examples:
廊下で走ってはいけないRouka de hashitte ha ikenai.Don’t run in the hallway.
電車で食べてはならないDensha de tabete ha naranai.Don’t eat on a train.
車の中で大きな声を出してはだめKuruma no naka de ookina koe wo dashite ha dame.Don’t speak loudly in the car!


Now that you’re a pro at “must not” we can learn how to express “must”.

The reason you learned “must not” first is because in Japanese, “must” is expressed using a double negative. Think of it as “You must not, not ___.”

Make the verb negative, add the “must not” endings and you’re sorted. 

The structures are as follow:


Negative て te verb + は + だめ/いけない/ならない
Negative verb + と + だめ/いけない/ならない
Negative verb + ば
+ だめ/いけない/ならない

これから夕食を食べなければならないKore kara yushoku wo tabenakereba naranai.I have to eat dinner now.
くそっ!行かなくてはだめKuso! Ikanakute ha dame!Crap! I have to go!
View More Examples:
明日、お医者さんに行かないといけないんです。Ashita, oisha san niikanaitoikenai n desu.I have to go to the doctors tomorrow.ん beforeです gives the sentence an explanatory feel.
宿題をやらなければならないShukudai wo yaranakereba naranai.I have to do my homework.やる is the informal way to say する.
自分のやっている仕事を終わらせなければならなかった。Jibun no yatte iru shigoto wo owarasenakereba naranakatta.I had to finish the work I was doing.The causative form is used to give it a “to bring to an end” meaning.
恋人のために夕食を作らなければならなかった。Koibito no tame ni yushoku wo tsukuranakereba naranakatta.I had to make dinner for my girlfriend.


In casual speech we can finish a verb with と in order to imply “must”.

We can also change the ending slightly and not add だめ/いけない/ならない.

If you live in Japan, these are the forms that you’ll probably hear the most:

Negative て te verb + はなくて changes to なくちゃ and stops there.
Negative verb + とLeave the endings off.
Negative verb + ば baなければ changes to なきゃ and stops there.

Let’s see some examples:

何か飲まなきゃ.Nani ka wo nomanakya.I’ve gotta drink something now.
もう帰らないMou kairanaito. I’ve gotta go home.
View More Examples:
痩せなくちゃYasenakucha.I’ve gotta lose weight.
明日は早く会社に行かないAshita wa kayaku kaisha ni ikanaito.I’ve gotta go to the office early tomorrow.
試験のために練習しないShiken no tame ni renshuu shinaito.I’ve gotta practice for the exam.
もう辞めなきゃMou yamenakya.I’ve gotta quit.

NOTE || もう often used as it’s like saying “I’ve gotta ___ already.”

Think of it as “I’ve gotta ___ right now.”


If you’re not in an informal setting then you’ll be using いけない or ならない.

The good thing is that they’re both basically the same. But there is a slight nuance difference that you should be aware of.

  • いけない sounds more like you think that something must be done.
  • ならない sounds like you’ve been told to do it. 

This is a nuance to really worry about when you get to JLPT N1 level. As of now, in the early stages of your studies, it is not too important.


Here’s a quick recap of everything we taught you in this lesson:

Must notVerb て + だめ, いけない or ならない.
MustNegative て verb + は + だめ, いけない or ならない.
MustNegative verb + と + だめ, いけない or ならない.
MustNegative verb + ば + だめ, いけない or ならない.


  • Often “must” is expressed without だめ , いけない or ならない.
  • Slight difference between いけない and ならない but don’t worry for now. 

Learn Japanese with FlexiClasses

Book online classes with the best teachers in the industry.


How to say Must in Japanese?

Must in Japanese is expressed using a double negative. Think of it as “You must not, not ___.”

Make the verb negative, add the “must not” endings and you’re sorted. 

The structures are:

Negative て te verb + は + だめ/いけない/ならない

Negative verb + と + だめ/いけない/ならない

Negative verb + ば + だめ/いけない/ならない


これから夕食を食べなければならない。 kore kara yushoku wo tabenakereba naranai. | I have to eat dinner now.

背筋を伸ばさないといけませんね。 sesuji wo nobasanaitoikemasenne. | I have to stretch out my back.

How to say Must Not in Japanese?

To say must not in Japanese the structure is as follow:

Add は (wa) to the て (te) form of a verb and stick on だめ (dame), いけない (ikenai) or ならない (naranai).

食べる → 食べて + は + だめ = 食べてはだめ

食べる → 食べて + は + いけない = 食べてはいけない

食べる → 食べて + は + ならない = 食べてはならない


電車で食べてはならない。densha de tabete ha naranai. | Don’t eat on a train.

廊下で走ってはいけない。rouka de hashitte ha ikenai. | Don’t run in the hallway.

How to say Should in Japanese?

There are a few ways to say Should in Japanese.

1) はず (hazu) is used to express things that should (supposed to) be or should’ve been:

休日のはず (kyuujitsu no hazu.) | It should be (is supposed to be) my day off.

2) べき (beki) means “should” as in, “You should do ____.”

But it comes across as very bossy and know-it-all. For this reason, it’s rarely used to give someone advice.

お客様に敬語を使うべきです。okyaku sama ni keigo wo tsukau beki desu. || One should use polite language with customers.

3) 方がいい (hou ga ii) is used when you’re giving someone advice or telling them what to do. 

鬼滅の刃を読んだ方がいい。kimetsu no Yaiba wo yonda hou ga ii. || You should read Demon Slayer.

How to express can’t help but in Japanese?

ずにはいられない (zu ni ha irarenai) means can’t help but in Japanese.


– take the ない nai form of a verb,

– take off the ない nai,

– stick on ずにはいられない zu ni ha irarenai

– and you’re there!

The ず zu form is used in writing, but in speaking we’d say ないではいられない nai de ha irarenai.



Kodomo wo ki no doku ni omowazu ni ha irarenakatta no da.

I couldn’t help but feel sorry for the children.

Can I learn Japanese online with LTL?

Absolutely! We offer online Japanese lessons on our Flexi Classes platform.

Choose your level, study topic and study time, and you’re good to go!

Check out our 7 Day Free Trial to start your learning journey.

Can I learn Japanese in Japan with LTL?

Yes you can!

We offer group and individual classes in Tokyo, for the duration of your choice.

You can even stay with a homestay family to really immerse yourself in the Japanese culture and discover a Japanese’s family lifestyle.