Recall that decir (to say or to tell) is irregular in the preterite. For irregular verbs in the preterite, you must memorize their conjugations. (yo) dije(nosotros) dijimos (tú) dijiste(vosotros) dijisteis (él/ella/Ud.) dijo(ellos/ellas/Uds.) dijeron
The verb poder (to be able to, can) is also irregular in the preterite. The verb poder is often followed by an infinitive to say what you could (and did) do or couldn’t (and, in fact, didn’t) do. yopude tútúpudiste él, ella, ud.pudo nosotros(as)pudimos vosotros(as)pudisteis Uds., ellos, ellaspudieron
Traer (to bring) is another irregular preterite. yotraje tútútrajiste él, ella, Ud.trajo nosotros(as)trajimos vosotros(as)trajisteis Uds., ellos, ellastrajeron
Ana no pudo venir a clase ayer porque se enfermo. Ana couldn’t (didn’t) come to class yesterday because she got sick. Pude terminar la tarea en una hora. I was able to (and did) finish the homework in an hour. Traje el helado para la fiesta. ¿Que trajiste tú ? I brought the food for the party. What did you bring?