北宋初年，宋太祖加强中央集权主要是因为 （   ）

A．陈桥兵变

B．唐后期藩镇割据

C．唐末农民战争

D．五代的频繁更替

按要求变化句型。

1. I came here to return the money.(对划线部分提问)

_____ _____ you come here _____?

2. Oxfam Trailwalker is a tough charity walk.(对划线部分提问)

_____ _____ Oxfam Trailwalker?

3.The charity walk held every month.(对划线部分提问)

_____ _____ is the charity walk held?

4. I think it's impossible for him to finish it in ten minutes.(改为反意疑问句)

I think it's impossible for him to finish it in ten minutes, _____ _____?

5. It's fun to play with them.(改为感叹句)

_____ _____ it is to play with them.