para siempre in inglese:

I'm leaving for good and I'm not coming back.

She left her family for good and never came back.

Are you here for good?

Nobody in the class liked the girl who moved. They all hope she's gone for good.

It looks like Jamie has left for good this time.

I finally left home for good.

Jane has gone to France - for good. She's not coming back.

to stop smoking for good

She's given up smoking for good.

I think he settled in Warsaw for good.