声束穿过界面时方向发生改变，称做（）
A.入射角度
B.折射
C.正常反射
D.后散射
E.衰减
参考答案：B
根据句意及所给提示，补全单词或用单词、固定短语、固定搭配的正确形式填空。
1. She showed her great i ______ in writing stories at an early age.
2. He rushed out and carried the little boy to the ______ (safe) .
3. Who was electricity ______ (discover) by?
4. The price of the cabbage is much ______ (高) than before.
5. My cousin Wang Fang ______ (弹钢琴) when I went into her house.
提示左心室衰竭的是（）。
A.奇脉
B.迟脉
C.无脉
D.交替脉
E.水冲脉
