Река Кама впадает в великую русскую (река) Волгу. The Correct Answer:
For exercise 142 from the 8th-grade Russian textbook by , the focus is on identifying and correctly punctuating appositives (приложения)—a specific type of definition expressed by a noun. Exercise 142 Breakdown
If a common noun (like река ) comes a proper name ( Волга ), you generally do not use a hyphen.
A standard resource for checking Russian language homework for the Trostentsova 8th-grade curriculum.