句型转换，按照题后要求变换下列句子。

1. I have already cleaned the fridge. (变一般疑问句)

    ________ you cleaned the fridge ________?

2. Mr. Hawking began to teach physics in this school in 2000. (变同义句)

    Mr. Hawking ________  ________ physics in this school since 2000.

3. I want to go swimming, I don't want to stay at home. (变同义句)

    I'd _______ to go swimming ________ of staying at home.

4. He bought a book two days ago. (变同义句)

    He _______  ________ a book for two days.

5. They can hardly believe it. (变反义疑问句)

    They can hardly believe it, ________  ________?