ければ
nakereba

Expression

1. if (it) doesn't exist; if there is no ...; if (one) doesn't have ...

Usually Written in Kana
みずがなければ、何者 なにものもこの地球 ちきゅう じょうには きられないだろう。
mizuga nakereba nanimonomo kono chikyūjōniwa ikirarenaidarō.
Without water, nothing could live on this earth.
Auxiliary Verb
Expression

2. if not ...; unless ...

Usually Written in Kana
いそがなければ、学校 がっこう遅刻 ちこくしますよ。
isoganakereba gakkōni chikoku shimasuyo.
Unless you hurry, you will be late for school.
Auxiliary Verb
Expression

3. have to ...; must ...

Abbreviation
Usually Written in Kana
Related to なければならない
いそがなければ、急行 きゅうこう おくれるぞ。
isoganakereba kyūkōni noriokureruzo.
You must hurry up, or you will miss the express.