睾丸切除手术要求麻醉平面上界达到（）
A.T10
B.S5
C.L2
D.T6
E.T12
参考答案：A
Look and answer. (看图，仿照例子回答问题)
例: — Is he sad? — No, he isn't. He's happy.
1. — Is he happy? — _______________________________
2. — How do they feel? — ________________________________
小王每天到学校要爬一段有8阶的楼梯，他每次可以任跨1阶或2阶或3阶。例如：小王可以先跨3阶，再跨1阶，再跨2阶。试问小王总共有多少种方法爬这段楼梯______
A．24 B．44 C．81 D．149
— Is he sad? — No, he isn't. He's happy.
— Is he happy? — _______________________________
— How do they feel? — ________________________________