Answer:
Pretérito perfecto simple:
1. Nosotros descargamos programas en la red.
2. Los matemáticos descubrieron una fórmula revolucionaria.
3. La astrónoma observe el cometa durante horas.
4. Usted realice avances en la invertigación.
5. La ingeniera patentó el descubrimiento.
Explanation:
PRETERITO PERFECTO SIMPLE
The preterite tense is used to talk about actions that took place in the past and has no relation to the present.
The past perfect simple or past tense is formed based on the root of the verb (infinitive minus -ar, -er, or -ir) and adding the following disinherities:
* Verbs of the first conjugation (ending in -ar): -é, -aste, -ó, -amos, asteis, -aron * Verbs of the second and third conjugation (ending in -er or -ir): -í, -iste, -ió, -imos, -isteis, -ieron
