Hello,
My friend wants to start learning English from 0 :) Could someone recommend good textbook for him ? Maybe you have one and could share with us :) I would be thankful.
google the following words:
archive.org english grammar
And look there. Archive.org is a place where people send books, music, movies,... without copyright, though I imagine there are some mistakes in copyright. Hope you may find there some good books. Good luck!