Sometimes foreign language acquisition is not an easy task. Keeping that in mind, the RBC launched, in PDF format, a series of three books called Só Verbos , written by Airamaia Chapina Alves, about verb conjugations. The first volume deals with the present tense. The second volume reviews the content of the first one and introduces the Simple Present time/duration variations as well as its passive forms.
The third volume introduces the Subjunctive and other tenses used in Portuguese. There are also verb conjugation charts and exercises for student practice