Решение:
Нужно преобразовать утвердительные предложения в отрицательные, используя вспомогательные глаголы 'do/does/did' или 'to be'.
- We do not (don't) play the piano. (Present Simple, отрицание с 'do not').
- The cat does not (doesn't) drink milk every day. (Present Simple, 3-е лицо ед.ч. - 'does not').
- They are not (aren't) drinking Cola. (Present Continuous, отрицание с 'are not').
- You do not (don't) walk to school. (Present Simple, отрицание с 'do not').
Ответ: We don't play the piano; The cat doesn't drink milk every day; They aren't drinking Cola; You don't walk to school.