While Schubert doesn't give away their B1 Arbeitsbuch PDF for free, they offer a massive (Internet-Übungen) for free.
(coursebook) introduces concepts, vocabulary, and grammar, the workbook is where the actual labor of learning takes place. It offers the repetitive, targeted practice required to internalize complex German grammar structures—such as the passive voice, subjunctive II ( Konjunktiv II ), and advanced subordinate clauses. Why Learners Search for "PDF Free"
The term "Arbeitsbuch" (workbook) signifies a specific type of educational tool. Unlike a textbook ( Lehrbuch ), which often introduces concepts through narrative and explanation, a workbook is a practical instrument. It is the training ground where grammar rules are tested, vocabulary is reinforced through repetition, and listening comprehension is honed. The inclusion of "B1" in the search query highlights the learner's specific stage of progress. According to the Common European Framework of Reference for Languages (CEFR), B1 represents a threshold level—the point at which a learner can understand the main points of clear standard input and deal with most situations likely to arise while travelling. Therefore, the search for a B1 workbook is the search for a bridge: a tool required to cross from being a tourist in the language to being a resident.