Resultados posibles:
respaldabas
-you were backing
Imperfecto para el sujeto del verbo respaldar.
respaldabas
-you were backing
Imperfecto para el sujeto vos del verbo respaldar.

respaldar

Solo queríamos asegurarnos de que nos respaldabas.
We just had to make sure you had our backs.
Dijiste que me respaldabas.
You said you had my back.
Creí que me respaldabas.
I thought you had my back.
¿Tu la respaldabas a ella?
Did you support her?
Palabra del día
la aceituna