Author with email in blog/news widget template

Hello,

I want to add the author's email in the blog/news summary but I'm not sure how to do it. I would also love to translate the text "by" <author> but I'm also don't know how to do it. I tried to change the text in the code 

but of course it ends in an error (but that's how I translated the "full story" text).

I hope I was clear enough :)

Bor