In other words, unlike the present perfect tense which states an action that ... (Two actions: writing and advising.) The examples show that some people confuse has/have with had because they ...

First though, we need to know how haber is formed in the present tense. he, has, ha, hemos, habéis, han. Here’s an example of the perfect tense in use: Ha ganado la carrera. - ‘She has won ...

The abstract is usually in the past tense due to it showing what has already been studied. Example: “This study was conducted at the Iyarina Field School, and within the indigenous Waorani community ...