split-seconds chronograph

例句：

1. 1.The watch has a split-second accuracy.
   这手表的精确度是毫秒级的。
2. 2.He used the chronograph to time his jump.
   他用秒表计时跳了一次。
3. 3. The chronograph was used in ancient times to measure time.
   秒表在古代用来测量时间。