This is a regular verb. It follows the conjugation pattern of the verb falar.
Present:
A Ana recusa a oferta.
Ana refuses the offer.
Preterite:
O Miguel se recusou a assinar o contrato.
O Miguel recusou-se a assinar o contrato.
Miguel refused to sign the contract.
Conditional:
A Clara recusaria essa proposta.
Clara would refuse that proposal.