occupés

In a sentence

• Les enfants sont très occupés avec leurs devoirs.

  The children are very busy with their homework.

  In this sentence, 'occupés' is used as an adjective to describe the children being engaged in activities (doing homework).

• Nous sommes occupés à préparer la fête.

  We are busy preparing the party.

  Here, 'occupés' functions to convey that the subject (we) are actively involved in the action of preparing.

• Les sièges ne sont pas occupés.

  The seats are not occupied.

  In this case, 'occupés' indicates the state of the seats, meaning they are not taken or filled by anyone.