患儿，男性，9岁，上前牙外伤8小时后就诊。检查：右上1已萌，松动Ⅰ，叩痛（+），纵向冠根折断，露髓，舌侧呈游离状。

如果X线检查发现左上1嵌入，未见骨折线，处理方案为（）

A.即刻复位

B.拔除患牙

C.定期观察

D.正畸牵引复位

E.不予处理

按要求改写句子。

1. He speaks English better than any other student in the class. (改为同义句) 

    He ____ ____ ____ ____ his class.

2. I think Eliza is the best performer. (对画线部分提问)

    ____ ____ ____ ____ is the best performer?

3. They sang a cute song together. (改为否定句)

    They ____ ____ a cute song together.

4. The dog lies on the ground. (用now改写)

    The dog ____ ____ on the ground ____.

5. Beijing is very hot in summer. (对画线部分提问)

    ____ ____ ____ ____ in summer in Beijing?