用所给词的正确形式填空。

1. The little boy fell off the tree and _____ (hurt) himself seriously.

2. She died after a long _____ (ill).

3. Doing eye exercises _____ ( be) good for your eyes.

4. Reading _____ (make)me happy.

5.There are many _____ (different)between the countryside and the big city.

我国经济发展正处于增长速度换挡期、（）阵痛期、前期刺激政策消化期“三期叠加”阶段。

A.转变方式

B.经济转型

C.社会转型

D.结构调整