centimeter per second per second

例句：

1. 1. Thedistance between the two points is20 centimeters per second.
   两点之间的距离是每秒20厘米。
2. 2. The caraccelerated to 60 km/h in less than a second.
   汽车在不到一秒的时间内加速到每小时60公里。
3. 3. The scientist measured the temperature with athermometer every second.
   科学家用温度计每秒钟测量温度。