"We are going to change."
Translation:Nós vamos mudar.
I'm not sure how does it sound to a native speaker, but it is wrong for phrasal future. There is a difference between Portuguese and Spanish here:
Both languages have a construction similar to the English "going-to" future. Spanish includes the preposition a between the conjugated form of ir "to go" and the infinitive: Vamos a cantar 'We're going to sing' (present tense of ir + a + infinitive). Usually, in Portuguese, there is no preposition between the helping verb and the main verb: Vamos cantar (present tense of ir + infinitive). This also applies when the verb is in other tenses:
- Ayer yo iba a leer el libro, pero no tuve la oportunidad. (Spanish)
- Ontem eu ia ler o livro, mas não tive oportunidade. (Portuguese)
- Yesterday I was going to read the book, but never had the chance.