Поставьте предложение в вопросительную и отрицательную форму
1. My sister is playing the piano now. 2. The teacher is explaining the rule. 3. We are learning the new words. 4. Ann is standing at the window. 5. We are going to the park 6. John is taking a piece of chalk and writing a sentence on the blackboard. 7. I am doing my homework. 8. Jane is speaking on the telephone. 9. She is cooking supper.