1. (2016·黔西南) 句型转换。

1. （1） She must be a doctor,  ?（完成反意疑问句）
3. （2） China has a population of 1.37 billion.  （对划线部分提问）

     the population of China?

5. （3） It took him one and a half hours to finish the task.(变成同义句)

   He  one and a half hours  the task.

7. （4） Now, more and more foreigners speak Chinese well.（变为被动语态）

   Now, Chinese   by more and more foreigners well.

9. （5） I find it difficult to learn physics.（变成复合句）

   I find   to learn physics.