句型转换。

1. Climbing is not so dangerous as diving. (保持句意基本不变)

    Diving is _____________ dangerous _______________ climbing.

2. Millie's shoes are not the same as Tina's. (保持句意基本不变)

    Millie's shoes are ____________ ____________ Tina's.

3. David is polite and helpful.(就划线部分提问)

     _____________ is David ____________?

4. We can go to the Summer Palace by bus. (保持句意基本不变)

    We can ____________ a ___________ to the Summer Palace.

5. They did their homework last night. (改为否定句)

    They ____________ ____________ their homework last night.