You're looking for the Spark 4 Students Book in PDF format!
Spark 4 Student's Book is an English language textbook part of a multi-level course published by Express Publishing
The Student's Book is part of a larger ecosystem of materials designed to provide a comprehensive learning experience [1].
Students can carry their entire textbook on a tablet, smartphone, or laptop.
Express Publishing frequently offers free PDF sample chapters on their official website so you can preview the content.