P or I ?
did it once
P
Preterite
yo bailar preterite
bailé
yo bailar imperfect
bailaba
aste
tú "ar" preterite
bailamos
we danced
Used to do it
I
Imperfect
tú bailar preterite
bailaste
ella escribir imperfect
escribía
aron
ellos or ellas "ar" preterite
bailábamos
we used to dance
Ongoing past
I
Imperfect
ella correr preterite
corrió
tú correr imperfect
corrías
íamos
nosotros er/ir imperfect
corriste
you ran
Definite start and end in past
P
Preterite
yo escribir preterite
escribí
Uds. bailar imperfect
bailaban
í
yo er/ir preterite
corrieron
they or y'all ran
Ongoing situation interrupted by something in the past
I & P
Imperfect interrupted by Preterite
ellos escribir preterite
escribieron
Marco y yo correr imperfect
corríamos
ías
tú er/ir imperfect
y'all used to write
Uds. escribían