⚠️ Ser and ir share EXACTLY the same forms in the indefinido — context tells them apart: Fui al cine (I went to the cinema) vs. Fui médico (I was a doctor).
Learn the stems as vocabulary: tuv-, estuv-, pud-, hic-, vin-, quis-. The endings are -e, -iste, -o, -imos, -isteis, -ieron — no accent marks! Note: hacer → él hizo (c→z before o to preserve the soft sound).
👩🏼📋 Ejemplos:
Fui al médico ayer por la tarde.
I went to the doctor yesterday afternoon.
Tuvimos que esperar más de una hora.
We had to wait more than an hour.
No pude dormir bien anoche por el ruido.
I couldn't sleep well last night because of the noise.
Hice todo lo que me pediste antes de las tres.
I did everything you asked me before three o'clock.