a.m.和p.m.的全称分别为拉丁语ante meridiem和拉丁文post meridiem。a.m.和p.m.对应的都是拉丁文词汇，其中a.m.中文翻译为“午夜至正午”、“上午”、“午前”；p.m.中文翻译为“下午”、“午后”。
一、a.m.的含义及双语例句
a.m.源自拉丁语ante meridiem，意为午夜至正午，上午，午前。
例句：It starts at 10 a.m.
上午10点开始。
The Visitor Centre is open daily 8.30 a.m. – 4.30 p.m.
游客中心每日上午8:30至下午4:30开放。
The fire reached its height around 2 a.m.
大火在半夜两点钟左右烧得最猛。
The telephone roused me from my sleep at 6 a.m.
早晨6点钟，电话铃声就把我从睡梦中吵醒了。
Guests should vacate their rooms by 10.30 a.m.
旅客应在上午10:30以前腾出房间。
Two people in the flat recalled hearing a loud crash about 1.30 a.m.
公寓楼里有两个人回想起凌晨1点半听见了一声巨响。
二、p.m.的含义及双语例句
p.m.源自拉丁文post meridiem，意为下午，午后。
例句：The spa closes at 9:00 pm.
休闲健身中心晚上9点关门。
The train departed Amritsar at 6.15 p.m.
火车在下午6点15分离开了阿姆利则。
The House rose at 10 p.m.
下议院于晚上10点钟散会。
At six p.m. large groups poured from the numerous offices.
下午6点钟大群大群的人从无数办公楼里蜂拥而出。
