Regular Verbs
You went
fuiste or fue
They were
fueron
they put
pusieron
We were ('temporary' condition)
estuvimos
You (singular) wrote
escribiste or escribió
she could (was able to)
pudo
I brought
traje
y'all wanted
quisieron or quisisteis
You (Ud.) had
tuvo
Why is there a spelling change in the yo form of these verbs?
In order for the conjugated form to sound like the infinitive (and keep the hard consonant sound), the spelling must change slightly.