"My husband never sleeps on the sofa, but I do."
Translation:Meu marido nunca dorme no sofá, mas eu durmo.
This kind of sentence cant be taken literally. As in English you use 'do' in place to the previoualy mentioned verb, in Poetuguese we have to use the verb again, if we think thats necessary. 'Fazer' (do) would be understandable, but not very used. Another way would be: "meu marido nunca dorme no sofá, mas eu SIM". its a very common way to say that