Genki Grammar #75: Mastering -nakereba ikemasen / nakya ikemasen

Introduction

In this blog post, we will learn about the Japanese grammar patterns: -なければいけません (nakereba ikemasen) and -なきゃいけません (nakya ikemasen). These patterns are used to express that it is necessary to do something, or “must.” Let’s explore how to use them!

What It Means

The patterns -なければいけません (nakereba ikemasen) and -なきゃいけません (nakya ikemasen) both mean “must” or “have to.” The なければ (nakereba) variant is more formal and often used in writing, while the なきゃ (nakya) variant is very colloquial and commonly used in speech.

When You Use It

Use -なければいけません / -なきゃいけません when you want to:

1. Express that something is necessary to do.
2. Indicate that there is an obligation or requirement.

Examples

Here are some examples to help you understand how to use -なければいけません / -なきゃいけません:

試験があるから、勉強しなければいけません / なきゃいけません。
(Shiken ga aru kara, benkyō shinakereba ikemasen / nakya ikemasen.)
I have to study because there will be an exam.

食べなければいけません / 食べなきゃいけません。
(Tabe nakereba ikemasen / tabe nakya ikemasen.)
I have to eat.

言わなければいけません / 言わなきゃいけません。
(Iwa nakereba ikemasen / iwa nakya ikemasen.)
I have to say it.

しなければいけません / しなきゃいけません。
(Shinakereba ikemasen / shinakya ikemasen.)
I have to do it.

こなければいけません / こなきゃいけません。
(Kona kereba ikemasen / kona kya ikemasen.)
I have to come.

Note

• Formal and Informal: Use なければいけません (nakereba ikemasen) for more formal situations and writing. Use なきゃいけません (nakya ikemasen) for casual speech.
• Literal Meaning: なければ (nakereba) and なきゃ (nakya) mean “if you do not do…” and いけません (ikemasen) roughly means “you cannot go.” Together, they mean “you cannot go not doing…” which implies “must.”
• Verb Conjugation:
  • 食べる (taberu) → 食べない (tabenai) → 食べなければいけません / 食べなきゃいけません (tabenakereba ikemasen / tabenakya ikemasen)
  • 言う (iu) → 言わない (iwanai) → 言わなければいけません / 言わなきゃいけません (iwanakereba ikemasen / iwanakya ikemasen)
  • する (suru) → しない (shinai) → しなければいけません / しなきゃいけません (shinakereba ikemasen / shinakya ikemasen)
  • くる (kuru) → こない (konai) → こなければいけません / こなきゃいけません (konakereba ikemasen / konakya ikemasen)
• Past Tense: You can change いけません (ikemasen) to いけませんでした (ikemasen deshita) to say “had to.”
  • 今朝は5時に起きなきゃいけませんでした。
    (Kesa wa go-ji ni okinakya ikemasen deshita.)
    I had to get up at five this morning.
• Short Form: In casual speech, you can use the short form なきゃいけない (nakya ikenai) or simply なきゃ (nakya).
  • 彼が来るから、部屋を掃除しなきゃ。
    (Kare ga kuru kara, heya o sōji shinakya.)
    I must clean the room because my boyfriend is coming.

Conclusion

The -なければいけません / -なきゃいけません (nakereba ikemasen / nakya ikemasen) patterns are essential for expressing necessity and obligation in Japanese. Understanding when to use the formal and informal versions will help you communicate more effectively.