a bouncing ball

• 跳动的球

a bouncing ball的用法和样例：

例句

1. She took a deep breath to calm her racing pulse.
   她深深地吸了口气，想使急速跳动的脉搏平静下来。
2. A cork, bobbing on water as waves pass by, is not swept away.
   当水波通过时，在水面上跳动的软木不会被冲走。