clock period

例句：

1. 1.The clock is set for 9:00 AM.
   时钟设定为上午九点。
2. 2.The watch has a 30-minute clock period.
   这只手表有30分钟的计时间隔。
3. 3. The clock was running out of battery, so we had to stop it.
   钟表没电了，所以我们不得不停下来。