Ответ:
1. Who is this girl? — She is my sister. — What is she? — She is an economist.
2. How does she know German? — She knows it very well.
3. When does your son do his lessons? — In the evening.
4. How does your son study? — He studies very well.
5. You don’t know these words, repeat these words and grammar rules at home.
6. Who of you is an economist? — Petrov is.
7. Who of you studies well? — Anna does.
8. Who gets the English magazines? — Ivanov does.
9. You usually read well, but now you are reading very bad.
10. Do you like to get letters?
11. He does not like to write letters.
12. We like to speak English at the lesson.
13. She does not like to repeat grammar rules .
14. She does not like to repeat the words after the teacher.
15. They like to read in the evening.
16. She seldom comes to the lessons in time.
17. She always comes to work in time.
18. How do you usually get there?
19. We will talk about it next week.
20. How often do you do your lessons together? — We do it every day.