One of the most comprehensive portals. You can find sections specifically for the Kuzovlev Reader (example for 5th grade) with answers for every lesson and exercise.
Provides high-quality, modern interactive solutions for Kuzovlev's textbooks and reading materials. gdz po anglijskomu jaziku reader kuzovleva
If you are looking for the official keys used by teachers, these are often found in the . You can sometimes find PDF versions of these on educational forums or sites like VK groups for English teachers . One of the most comprehensive portals