1. was
2. studied
3. returned
4. worked
5. married
6. had
7. discovered
8. received
9. died
10. was
11. died
12. buried

Irregular verbs: be → was/were, have → had

Verified answer

1. was

2. studied

3. returned

4. worked

5. married

6. had

7. discovered

8. received

9. died

10. was

11. died

12. buried

1, 6, 10 — неправильные глаголы.