Tests and Drills in Spanish Grammar: Book 1

For the last ten years I have used this book with great success.Frankly I Still have not found another book on sale here in Argentina to substitute it. Lately it has not been on sale and unfortunately the issue of BOOK 1 in my possesion is wrongly bound. This means that Units 13, 14 and 15 are missing and instead three units of Book 2 are included. The book in my possesion has been published by Regents. I WISH YOU COULD HELP ME SOLVE THIS PROBLEM

I am a Spanish language teacher at a college in Australia. For the past teen years this book has been my Bible in organising my classes. And my sever when I have to look for any answer to those questions that arise once in a while, that I'm not sure of the answer. I had try lots of different books to review, but nothing goes as good explaining the difficult grammar as this books does, using the most simplicity to explains it, you can expect any simpler. I'm Spanish born person.