Notice that:
1. Verbs ending in –er and -ir have the same endings.
2. The “nosotros” forms for -ar and -ir verbs are the same in the preterite and present tense, therefore you will have to pay attention to the “temporal expressions“:
Nosotros siempre hablamos español (We always speak Spanish).
Ayer hablamos español en una reunión importante (Yesterday we spoke Spanish in an important meeting).
Normalmente escribimos muchos mensajes en el trabajo (We usually write many emails at work).
Anteayer escribimos un mensaje muy importante (The day before yesterday we wrote a very important email).
3. Especially relevant is the accent in “yo, él, ella, usted“, it will help us not to mistake the preterite tense with the present or the imperative:
Ramón compró un libro (Ramon bought a book).
Compro muchos libros (I buy many books).
Escuché la noticia en la radio (I listened to the news on the radio).
Sr. Fernández, escuche la noticia (Mr. Fernández, listen to the news).
4. The PRETERITE is used to describe a complete action in the past, for example when in English you say “did something”.
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