Найдите в предложениях Present Perfect, Past Perfect, Future Perfect.
Переведите предложениях на русский язык.
1. About 75 percent of students receive state grants and 15 percent have been
sponsored by enterprises.
2. That the problem of pollution and ecology had become the most important
for mankind is evident to all.
3. They will have finished the experiment by 12 o’clock tomorrow.

1. have been sponsored - Present Perfect

Около 75 процентов студентов получают государственные гранты, а 15 процентов - спонсируются предприятиями.

2. had become - Past Perfect

То, что проблема загрязнения окружающей среды и экологии стала самой важной для человечества, очевидно для всех.

3. will have finished - Future Perfect

Завтра к 12 часам они завершат эксперимент.

1. did you

no, i didn't.

2. didn't you

yes, i did.

3. wasn't it

yes, it was.

4. didn't they

no, they didn't.

7. did you

no, i didn't.

8. hadn't you

yes, i had.

9. could you

no, i couldn't.

10. weren't they

yes, they were.

11. were you

no, i wasn't.

12. did you

no, i didn't. 

13. did you

yes, i did.

14. did you  

no, i didn't.

15. did you

yes, i did.