donc

In a sentence

• Je suis fatigué, donc je vais me reposer.

  I am tired, so I am going to rest.

  In this sentence, 'donc' is used as a conjunction meaning 'so', establishing a cause-effect relationship between being tired and deciding to rest.

• Il est assez tard, donc nous devrions peut-être partir.

  It is quite late, so maybe we should leave.

  Here, 'donc' connects the observation that it is late to the suggestion of leaving, again indicating a reason-consequence relation.

• Tu as étudié dur; donc, tu as réussi à l'examen.

  You studied hard; therefore, you succeeded in the exam.

  In this usage, 'donc' serves as a transitional adverb equivalent to 'therefore', marking a formal conclusion drawn from the first clause.