müssen

In a sentence

• Ich muss jeden Tag zur Arbeit gehen.

  I have to go to work every day.

  Here, 'muss' is used to express an obligation or necessity that applies to the subject 'ich' (I).

• Er muss morgen früh aufstehen.

  He has to get up early tomorrow.

  Here, 'muss' is used to indicate a necessity or requirement for the subject 'er' (he).

• Wir müssen die Hausaufgaben rechtzeitig erledigen.

  We need to complete the homework on time.

  Here, 'müssen' is used in the first-person plural form to express a responsibility or obligation.