"If you can't be good, be careful"
Mi padre decía: "¡Si no puedas ser buena, ten cuidado!"
My father used to say, "If you can't be good, be careful!"
Please correct my Spanish translation. I am uncertain about:
Is my use of the verb "decía" in the imperfect correct to express that my father used to say this, or do I need to say something else, or something more?
Is my use of the subjunctive and the informal command form correct?
Is there a better way to express the English "can't be good" than I have used - it's a bit word-for-word and I always wonder about that.
Many, many thanks!
¡Muchas, muchas gracias!
EDIT: Many thanks to Feliz and Guillermo. Based on their advice:
Mi papá nos decía: "¡Si no puedes ser buena, ten cuidado!"
Any other suggestions are very welcome!
3 Answers
You are perfectly correct in your use of the imperfect (tense) decía to express/communicate the idea that your father used to say this.
If he said it to you personally you could say:
Mi padre me decía = My father used to say this to me ...
You can also use the more familiar and affectioante form 'papá' (Dad) in place of padre which is quite formal but that is your choice, of course 
Following on from what Guillermo has just said:
You can either simply say Mi padre decía..(ie: to everyone) .etc...
or you could, from what you have just told me, say:
Mi padre nos decía = My father used to say to us
I hope that this helps You
Mi padre decía: "¡Si no puedes ser buena, ten cuidado!"
Feliz appreciation is correct, but there is a slight difference in saying "me decía". If you use "me decía" you are saying that he used ti say that to you. Not putting "me" is a more wide statement, like your father used to say that to everybody.
Just for fun! I heard this phrase in a movie recently.
"Pórtate bien, pero si te portas mal, ¡invítame!"
"Behave yourself, but if you misbehave, invite me!"
