What do you do when lost youre book but you're still told to do the same work

If you've lost your book, I highly advise you to tell your teacher, or whoever is teaching you. There is no literal way for you to do your work without the book. Although, there is an alternative. If you can find an online version of the book, then you don't need to ask, but if that's not an option, always ask.

Look off a friend, or google the book?