1. A dog is AN animal. 2. My sister plays piano beautifully. 3. Tim flies aeroplanes. He is A pilot. 4. Radio <span>was invented by Russian engineer Popov. 5. Wait! THE room is not vacant, </span><span>there are students in there. 6. In the morning Bill received A very </span><span>serious letter from THE boss. Now he is writing A reply letter. 7. I </span><span>took A taxi to THE station. 8. Have you got A camera? 9. What do you </span><span>usually have for dinner? 10. THE earth goes round THE sun.</span>