Avoiding Typical Errors With

Verb Tenses

The use of Present Perfect;

When an action started in the past and still happens in the present or an action that happened in an unspecific time in the past.

Ex: I have lived here for many years.

     I have been to London.

The act of mentally translating from Portuguese doesn't find a correpondence in English. The first sentence would be "Present do Indicativo" and the second "Pretérito". The way to avoid mistakes of this type is to think of the function (idea) the sentence shows.

Everytime you mention the period of time an action has happened or if the completed action doesn't show a "when", choose Present Perfect or Present Perfect Progressive.  ( see Verb Tense )