1) If the weather were better now, I would go (go) for a walk. If it had been (be) warmer last Sunday, we would have gone to the country.

Решение:

В данном задании нужно использовать глаголы в подходящей форме (Conditional II или III).

1. had been (be) warmer last Sunday, we would have gone to the country. (Conditional III: If + Past Perfect, would have + V3)
2. If you trained harder, you would win (win) the competition next week. (Conditional II: If + Past Simple, would + V1)
3. If I were (be) you, I would do sports and keep fit. (Conditional II: If + Past Simple, would + V1. Для 'be' в условных предложениях часто используется 'were' для всех лиц)
4. If people thought (think) more about the environment, nature protection wouldn't be such a serious problem now. (Conditional II: If + Past Simple, would + V1)
5. If the water in the river were polluted, there would be (be) no fish. (Conditional II: If + Past Simple, would + V1)
6. If you collected (collect) domestic rubbish into special bins, it would be recycled. (Conditional II: If + Past Simple, would + V1)
7. If you had learned new English words, you would write (write) the test better. (Conditional III: If + Past Perfect, would + V1)
8. If I had known (know) that you were ill last week, I would have gone to see you. (Conditional III: If + Past Perfect, would have + V3)
9. Jim would have gone (go) to the cinema with us, if he hadn't seen the film twice. (Conditional III: If + Past Perfect, would have + V3, но здесь часть с 'if' стоит после основного действия)
10. If I had taken (take) your address, I would have sent you postcard from London. (Conditional III: If + Past Perfect, would have + V3)
11. I would have forgotten (forget) about Sue's birthday, if Anna hadn't told me about it. (Conditional III: If + Past Perfect, would have + V3, но здесь часть с 'if' стоит после основного действия)