The “simple past” = action that is over and done. Officially called the Preterit Indicative tense.
| to eat | comer | ||
| I ate | eu com | i | |
| you/he/she ate | você/ele/ela com | eu | |
| we ate | nós com | emos | |
| they/you all ate | eles/elas com | eram | |
(eu) Eu entendi tudo. I understood everything.
(você, ele, ela) Ele nao entendeu. He didn't understand.