Nate bought a robot vacuum for his apartment last month. He set it to clean every day.
上个月，内特给他的公寓买了一台扫地机器人。他把它设成每天打扫。
For the first two weeks, everything worked well. The vacuum cleaned in the afternoon while Nate was at work.
头两个星期，一切都很顺利。内特上班的时候，机器人在下午打扫。
Then, one night, Nate woke up at three in the morning. He heard a strange humming sound.
后来，有一天夜里，内特凌晨三点醒了。他听到一阵奇怪的嗡嗡声。
He walked into the living room. The robot vacuum moved across the floor. It cleaned loudly.
他走进客厅。扫地机器人正在地板上移动，打扫的声音很大。
Nate turned it off and went back to bed, confused. The same thing happened the next night, and the night after that.
内特把它关掉，困惑地回去睡觉。第二天夜里，同样的事又发生了，第三天夜里也是。
The next morning, Nate opened the vacuum's app on his phone. He looked at the cleaning schedule.
第二天早上，内特在手机上打开了机器人的应用，查看清扫计划。
The schedule said "3:00 AM" every day. Nate never set that time.
计划上每天都写着“凌晨3:00”。内特从来没设过这个时间。
He checked the settings carefully. He saw a small mistake. He picked "AM" instead of "PM" when he first set it up.
他仔细检查了设置，发现了一个小错误。他最初设置的时候，选了“上午”，而不是“下午”。
Nate laughed at his own mistake. He changed the time to three in the afternoon.
内特对自己的错误笑了。他把时间改成了下午三点。
That night, the apartment stayed quiet. The vacuum cleaned the next afternoon, at the right time.
那天夜里，公寓里一片安静。第二天下午，机器人在正确的时间打扫了。
Nate never woke up to the sound of cleaning again.
内特再也没有被打扫的声音吵醒过。
