Sites like GDZ.ru often list supplemental materials for the 7th-grade Russian language curriculum, though they primarily focus on standard textbooks and workbooks by authors like Bystrova or Ladyzhenskaya.
The "Linguistic Simulator" (Лингвистический тренажер) for the 7th grade by is a popular workbook used in Russian schools to reinforce grammar, spelling, and punctuation skills.
If you are looking for a or a difficult rule (like N and NN in participles), let me know and I can explain the grammar rule behind it or help you solve it.
Finding official answer keys (GDZ) for this specific series can be difficult because they are often integrated into teacher-only manuals or updated frequently. However, you can find help through the following resources:
Formation, suffixes, and punctuation in participial phrases.
For specific exercises, students often upload photos of completed pages to community forums like Znanija (Znayka) or Uchi.ru , where peers and tutors verify the logic. Core Topics Covered in the 7th Grade Simulator:
Prepositions, conjunctions, and particles (specifically the distinction between ne and ni ).
ГДЗ по русскому языку за 7 класс, решебник и ответы онлайн