Focus on word structure (morphemics), vocabulary (lexis), and parts of speech.
Use the answers for verification rather than just copying; this is especially important in 9th grade to prepare for final exams. Which specific grade level or author gdz po russkomu iazyku klass uchebnik 2017 god
Below are the most widely used textbooks that had 2017 editions, along with where to find their solutions: Focus on word structure (morphemics)