alarm weight mass

例句：

1. 1. The alarm clock woke us up at 6:00 a.m.
   闹钟在早上六点叫醒了我们。
2. 2. We need to be more cautious when crossing the street.
   过马路时我们需要更加小心。
3. 3. The fire alarm went off in the building.
   大楼里的火警响了。