我们生活的大洲是（    ）

数列$\left\{a_n\right\}$中，$a_1=-1,a_{n+1}=a_n-3$，则$a_8$等于（　　）

如图，圆的半径是6，空白部分的圆心角分别是60°与30°，则阴影部分的面积是（     ）

 （A）

      Mary is an English girl, but shelives(居住) in China.She is six. Her mother says to her, "You are six now, Mary, you are going to school.I think it is very good. It's a nice school."

      "Is it a Chinese school?" Mary asks.

      "Yes, it is." Her mother says.

      It is September(九月) and the new school year begins. Marygoes to school every day. She likes her lessons（功课） and her classmates(同学)very much.Her classmates like her, too. Mary can speak a little Chinese. She likes China.She likes the people of China and Chinese food very much.