2.8 KiB
Obligation: なければ・ないと
Must
なくちゃ・なきゃ
Only used on casual spoken conversations. This form is used with the negative form of a verb (ない), and adding なくちゃ and optionally one of the following ending: だめ, いけない, いけません, ならない, なりません.
なくちゃ is the shortened form of なくては. なきゃ is the shortened form of なければ.
[!info] Example {歯|は}を{磨|みが}か==なくちゃいけない==。 I must brush my teeth.
なくては「いけない・ならない」
Also formed with the negative form of a verb.
[!info] Example 今{遅|おそ}いね。{寝|ね}に行か==なくてはいけない==。 It's late now. I have to go to sleep.
なければ「いけない・ならない」
Also formed with the negative form of a verb.
[!info] Example {事務所|じむしょ}では{静|しず}かにし==なければならない==。 You have to be quiet in the office.
ないといけない
Also formed with the negative form of a verb. In casual contexts, can be shortened as ないと.
[!info] Example 今日は{勉強|べんきょう}し==ないといけない==。 I have to study today.
Must not
「ちゃ・じゃ」「だめ・いけない・いけません」
Only used on casual spoken conversations. いけません is a bit more formal. This form is used with a V-て, depending on the ending:
- with て, ちゃ is used.
- with で, じゃ is used.
[!info] Examples その{花|はな}を食べ==ちゃだめ==。 Don't eat those flowers.
{花瓶|か|びん}の水を{飲|の}ん==じゃいけない==。 Don't drink the water of the flower vase.
てはいけない
Used in a more formal or written manner. Used with a V-て.
[!info] Example {鉄道|てつ|どう}に{歩|ある}い==てはいけません==。 Do not walk on the railroad.
Comparing いけない and ならない
- ==いけない== is the standardly used form. It implies a subjective view, that it would be better to do something, to avoid negative consequences (eg: brushing one's teeth, eating well, etc).
- ==ならない== is usually more formal or in written form. It implies a is more objective view, something that has to be done because there's no other way (eg: respecting the law, paying taxes, etc).
Comparing なくては, なければ and ないと
なくては and なければ are generally interchangeable in speech. However:
- ==なくては== is generally used when there is no penalty for not complying.
- ==なければ== is generally used when there is a penalty for not complying.
- ==ないと== is lighter and does not imply that there can or cannot be penalty. Its construction is based on the Conditional#と particle, and should be based on knowledge or experience.