hanamaru
Say you have to do something
This pattern says you have to do something.
JLPTN5
verb (nai-stem) + なければなりません[verb nai-stem] + nakereba narimasen
must do ~ / have to do ~
Take a verb's plain negative (the ない form), drop the final い, and add ければなりません. Use it for rules, duties, and things you cannot avoid. The shorter, more casual ending なきゃ means the same thing in everyday speech.
Tips and Common Traps
Hana· Key point
なければなりません sounds formal — great for rules and obligations. In daily conversation with friends, なきゃ or ないといけない feels more natural.
Maru· Common trap
The verb before なければなりません uses the ない-stem, not the dictionary form. For する (to do) the negative stem is し, giving しなければなりません (must do).