4. Use can/can't. 1. My grandfather is a very clever man. He ______ speak five languages. 2. I'm afraid I ______ come to your party next week. 3. I have plenty of time. I ______ go white water rafting. 4. My grandmother loves music. She ______ play the piano very well. 5. I feel sick. I ______ do anything.

Решение:

• 1. My grandfather is a very clever man. He can speak five languages. (Используем 'can', чтобы показать способность или умение).
• 2. I'm afraid I can't come to your party next week. (Используем 'can't', чтобы показать невозможность или отказ).
• 3. I have plenty of time. I can go white water rafting. (Используем 'can', чтобы показать возможность).
• 4. My grandmother loves music. She can play the piano very well. (Используем 'can', чтобы показать умение).
• 5. I feel sick. I can't do anything. (Используем 'can't', чтобы показать невозможность действия из-за плохого самочувствия).

Ответ: 1. can, 2. can't, 3. can, 4. can, 5. can't