This E-BOOK is aimed at beginners, level C1. It is directed primarily to adults, but definitely teenagers aged 16-19 can use it as well. Although ENGLISH 9 is a general language e-book, business and working people will find a lot of vocabulary related to work in it. The e-book has been prepared in the convention of the direct method. You can find out more about this method at this address: Direct Method
The price of the E-BOOK includes free access to mp3 recordings.