关于设备混凝土基础浇筑技术的说法，正确的有（）。

A.一般应分层浇筑，并保证上下层之间留置施工缝

B.分层混凝土浇筑厚度为400～500mm

C.分层浇筑顺序应从低处开始，沿长边方向自一端向另一端浇筑

D.也可采取中间向两端或两端向中间浇筑的顺序

E.对特殊部位，如地脚螺栓、预留螺栓孔、预埋管等，在混凝土浇筑过程中，应用经纬仪随时观测，发现偏差及时纠正

按要求改写句子。

1. There are some old nurses in the hospital. (改为单数形式) 

    There _______ _______ old nurse in the hospital.

2. There is only one reading room in the school. (对划线部分提问)

     _______ _______ reading rooms in the school?

3. The flowers are in the park. (对划线部分提问)

     _______ _______ the flowers?

4. They are some birds in the tree. (对划线部分提问)

     _______ _______ in the tree?

5. I go to school at seven thirty. ( 改为一般疑问句)

     _______ _______ go to school at seven thirty?