Would it be illegal if I made profit by translating some one else's blog?

and by posting in my own blog-of course stating where the source is- and putting ads in my blog?
Because I see some great stuff on the internet and I think it’s not fair to let it be there only for those who speak English.
And of course, it doesn’t hurt to earn some profit by doing that.
But as the original source of information is not from me, I wonder how this will sound to those in Fluther. Thanks!!