623 - ~てはいけない

They appear to love rules in Japan.

Or rather, they appear to love agreed-upon standards for how things should be done. This is how you stand when meeting someone. This is how you hold your business card. This is how you give your self-introduction. This is how every single person's resume should look.

Obviously Japan is not the only place with its own customs, rules, and guidelines. Living in Japan, though, the unwavering insistence on adhering to predetermined behavior in various situations can be a bit challenging for some foreigners.

Maybe you want to be sure that you are respectful while in Japan. Or maybe you want to rebel, rebel, rebel.

In either case, you'll need to know the language for stating rules in Japan...


JLPT N4: ~てはいけません ([you] must not; [you] should not; ...is prohibited)

The phrase ending ~てはいけない or ~てはいけません is used to tell someone that something is not allowed.

Accordingly, teachers use it toward students, parents use it toward children, and public signs use it toward everyone... when saying "you must not X" or "X is prohibited."

An example:


未成年はお酒を飲んいけません
みせいねん は おさけ を のんではいけません。
Minors [Underaged people] cannot drink alcohol.
Literally: “minor / underaged + は + alcohol + を + drink (and) + は + いけません.”


👷 Construction 👷

To say "X is prohibited" or "you must not X," we attach はいけません or はいけない to the て-form of a word.

The て-form word can be a verb, an i-adjective, a na-adjective, or a noun.

As a quick reminder, the て-form of a na-adjective or noun is just で, so...

V いけない・いけません
i-adjective くいけない・いけません
noun / na-adjective いけない・いけません

We'll see examples of all of these below...


Here is ~てはいけません being used with a verb:


友達の陰口を言っいけません
ともだち の かげぐち を いってはいけません。
You should never talk behind your friend’s back.
Literally: “friend + の + talking (negatively) behind someone’s back + を + say (and) + は + いけません.”


And here it is following an i-adjective:


離乳食はかたくいけません
りにゅうしょく は かたくてはいけません。
Baby food must not be hard.
Literally: “baby food + は + hard (and) + は + いけません.”


And here it is following a na-adjective:


公園の遊具は危険いけません
こうえん の ゆうぐ は きけんではいけません。
Playground equipment at parks must not be dangerous.
Literally: “park + の + playground equipment + は + dangerous + で + は + いけません.”


And here is it following a noun:


パスポートの原本は今は持っていません。コピーいけませんか。
パスポート の げんぽん は いま は もっていません。コピーではいけませんか。
I don’t have my actual passport with me right now. Is a copy unacceptable?
Literally: “passport + の + the original (copy) + は + now + am not holding. + copy + で + は + いけません + か.”

Notice anything different about that last example?

The speaker is not stating a rule but rather asking for permission or approval (to use a copy instead of his original passport).

Usually when we ask for permission, we use the ending ~てもいい(ですか)? (We'll have another N4 lesson on that in the future). But when we use ~てはいけません, instead, the speaker is able to give the request for permission the nuance of hesitation or doubt that the action will be permitted.

This makes sense. Negative requests in English tend to have the nuance of hesitation or doubt, too. For example, "Can I use a copy?" sounds a bit more direct than "Is a copy unacceptable?" or "Can I not use a copy?"


In spoken language, the ~ては of ~てはいけない often becomes ~ちゃ, giving us ~ちゃいけない.

Similarly, ~では becomes ~じゃ, giving us ~じゃいけない.

Here are examples of both:


道路にごみをちゃいけないんだよ。
どうろ に ごみ を すてちゃいけないんだよ。
You can’t throw your trash on the ground [in the street].
Literally: “road + に + trash + を + throw away (and) (ては → ちゃ) + いけない + んだ + よ.”


捨ていけない
↓ ↓ ↓
捨てちゃいけない


ガムは飲みこんじゃいけないよ。
ガム は のみこんじゃいけない よ。
You’re not supposed to swallow gum.
Literally: “gum + は + swallow (and) (では → じゃ) + いけない + よ.”
Note: 飲む means "to drink," but 飲みこむ means "to swallow."


飲みこんいけない
↓ ↓ ↓
飲みこんじゃいけない


That's it for this one.

Though I have come across this language on many, many, many occasions, I don't find myself using it all that often.

Maybe that will change someday if I have kids or start teaching rowdy classes of immature adolescents, though. *_*




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