有一读者说有这样一个句子：
(1)He had different clothes for every hour of the day.
他问到这里为什么用the day? day之前何时用a，何时用the，何时不用冠词？ days又如何用？
让我们先谈第一个问题，即这里为什么用the day的问题。我们知道“the+单形类名词”结构常可泛指一类事物，如：
(2)The doctor sees nothing but pain, pain, pain. （the doctor在此泛指医生）
(3)Several blinks will sometimes get a cinder out of the eye . （the eye在此泛指眼睛）
(4)The lion is the king of beasts. （the lion在此泛指狮子）
(5)The rose smells sweet. （the rose在此泛指玫瑰）
“the+单形抽象名词”结构同样也可以泛指一类概念，如：
(6)The wish is father of the thought . （the wish和the thought在此皆属泛指）
(7)The first half of the 19th century saw the duel die out. （the duel在此亦属泛指）
时间词，如hour, day, week, month, year等，也属于抽象名词。在它们之前冠以定冠词the亦可泛指某一时间概念。提问中的the day，即表泛指“一天”，再如下列句中的划线部分：
(8)Breakfast is the first meal of the day .
(9)She's paid by the day . （by the day是一习语，意谓“按工作日”）
(10)It's all in the day's work. （all in the day's work 亦一习语，意谓“不足为奇”）
(11)I went to a department store shortly before 7 p.m. as it was about to close for the day .
(12)On 14 March, seventy-three years to the day after Marx's death, the Memorial was unveiled. （to the day 亦一习语，意谓“一天不差地”）
除“the+day”可用以泛指外，还有“the+hour, week, month, year等”亦可用以泛指，实例如：
(13)The train arrives on the hour . （意谓“一小时一趟”）
(14)The week begins with Sunday.
(15)We pay the rent by the month .
(16)December is the last month of the year .
现在让我们分别探讨一下第二个问题：
1.“定冠词the+day”结构的用法除上述已讨论过的以外，还有如：
(17)The day was cold. （the day在此意谓“这一天”）
(18)Trousers are the order of the day for women when travelling now. （the order of the day是一习语，意谓“时尚”，the day在此意谓“当代”）
(19)It happened in the day . （the day在此意谓“日间”或“白天”，与the night相对）
2.“不定冠词 a(n)+day”结构的用法举例：
(20)Take the tablets three times a day . （a day在此相当于一天）
(21)We have stayed here for four months to a day . （to a day 相当于 to the day, 参见例[12]）
(22)He lived in a day when to be a gentleman had its obligations but also its privileges. （a day在此意谓“时代”或“时期”）
(23)An eight-hour day is common. （day 在此相当于 working day [工作日]）
3.“零冠词+day”结构的用法举例：
(24)Day was fading into dark. （day 相当于白天）
(25)Day breaks. （day 相当于日光，黎明）
(26)He asked me what was the time of day . （day在此指“一天”）
(27)Beijing was beautiful over National Day . （day在此指“节假日”）
关于第三个问题，同样我们也只能扼要地分别列述如下：
1.“定冠词+days”结构的用法举例：
(28)The days passed. （the days有所指，意味着“一天天”）
(29)As the days went by, she grew to feel that somehow it would be accomplished. （as the days went by是一常用结构，the days在此意味着“时间”或“时光）
(30)The days and the nights are of equal length at this time of year. （the days在此指“白天”，与the nights相对）
(31)He's going to tell us about his hard life in the old days . （days在此指“时期”或“时代”）
(32)“Those were the days ”, she sighed. “We didn't have a care in the world.” （the days在此指“昔日盛世”）
(33)The days have expired. （the days在此指“某人或事物的寿命”）
2.“零冠词+days”结构的用法举例：
(34)Days passed. （days在此指“多日”）
(35)Nobody has seen them for days . （days常与for连用，亦指“多日”）
最后，试看下一句中days与the days的区别：
(36)The hours had turned into days, the days had turned into weeks. （days在此泛指“日”，the days则指其前的days）
顺便提及， hour, week, month, year等时间词的用法，在许多方面都与day有相似之处。
