This is an irregular verb. It follows the conjugation pattern of the verb sair.
Present:
A Ana trai a confiança da amiga dela.
A Ana trai a confiança da sua amiga.
Ana betrays her friend's trust.
Preterite:
O Miguel traiu a equipe dele.
O Miguel traiu a equipa dele.
Miguel betrayed his team.
Conditional:
A Clara nunca trairia os valores dela.
A Clara nunca trairia os seus valores.
Clara would never betray her values.