a day! 前面用What. 还是 How 为什么啊？

a day 英[ei dei] 美[e de] [词典] 一天; It`s a sunny and nice day.这是美好的一天，阳光明媚。

一天day 英[deu026a] 美[de] n. 一天; 白天; 时期; 节日; adj. 日间的; 逐日的; adv. 每天; 经常在白天地; [例句]The weather did not help; hot by day, cold at night天气也不肯帮忙：白天很热，晚上很冷。

some day 指将来的某一天，可译作：“有朝一日，总有一天，改天，他日，某一天”; 在句中一般作时间状语。a day 指时间段“一天，一日，每天，每日”，可作主语、宾语; 或构成短语，如：twice a day每天两次，three times a day 每日三次。one day 常用来表示（过去或将来的）某一天，作时间状语； 可译作：“一天,有一天，某天，某日”（过去时间）； “有朝一日，总有一天”（将来时间），此用法与some day同义,可互换。 也可表示时间段“一天”，此用法与a day同义,可互换。例句：Some day I"ll be a pilot. 有朝一日，我会成为一名飞行员。 Some day he"ll be famous. 总有一天他会成名的。 There are twenty-four hours in a day. 一天有二十四小时。(a day作介宾） Please take the medicine three times a day . 请每日服此药三次。 It took him a day to paint the house . 他用了一天的时间来粉刷房子。(a day作直接宾语） A:How much time do you need to finish the work? A:你需要多少时间才能完成这项工作？ B:One/A day is enough. (One/A day作主语） B:一天就足够了。 One day I"ll be successful.总有一天，我会成功的。 One day he went to the forest...一天，他去到森林...(讲故事时，一般这样开头。） Puddings may be refrigerated for up to one day.（此句中的one day表示时间段“一天”） 布丁可在冰箱里冷藏长达一天的时间。

a day ＝24 hours，作为一个单位时间，它是一个名词短语，并未规定它不可以用在一般过去时里。如：I recently spent a day driving around the areas. (最近我花了一天的时间开车逛了这个地区。）a day 作宾语，spent 过去式。再如：In the past she still earned only 10 yuan a day. （ 过去她一天依然只挣10元钱。）a day 作状语，earned 过去式。

one day既有一天的意思，又有某天的意思。a day只有一天的意思，one day和a day在针对“一天”来说几乎相同。one day也可指过去的某天或将来的某天。 one day的用法 one day与some day均可用作状语，表示“有一天”，但两者所连用句子时态稍有区别： 1、one day可指过去或将来，即可用于过去时态或将来时态。如： One day the temperature was 30℃. 有一天温度达到30摄氏度。 I will [am going to] climb that mountain one day. 总有一天我要爬那座山。 One day people will be able to go to the moon on holiday. 总有一天人们可以到月球上去度假。 2、some day通常只指将来，即只用于将来时态。如： We"re all going to be old some day. 总有一天我们都会老的。 Some day I"ll come back and marry her. 总有一天我要回来娶她。 注：有时虽然不是将来时态，但句子意思表示的是将来意义。如： You"re sure to regret one day. 你准有一天会后悔。 I want to get married one day. But before that, I want to travel. 总有一天我要结婚。但在那之前，我要旅游。 另外，在特定语境中some day有时可指过去将来。如： I never realized that some day I would be living in China. 我从未想到将来有一天会在中国居住。

every day 意为每天，常作状语，如：I go to school every day.a day意为一整天，或某一天，如：A day to be remembered in my life.

一天和每一天

<A DAY>歌词大意 翻译：DOOPNEY [文字版][DoneHae] ub10c ubb3buc9c0 ud56duc0c1 uc5bcub9c8ub098 ub110 uc0acub791ud558ub294uc9c0 你一直问我有多爱你[RyeoWook] uac00ub054uc529 uc544uc9c1 uba3c ubbf8ub798uae4cuc9c0 ubd88uc548ud574ud558uc9c0偶尔会因为遥远的未来而感到不安 [YeSung] uac71uc815ud558uc9c0ub9c8 ub110 uad34ub86dud788uc9c0ub9c8 不要担心 不要有困扰ub0b4uac90 uc644ubcbdud55c uc0acub78cuc778uac78 对我来说你的一切都很完美[KyuHyun] uc228ub9cc uc26cuc5b4ub3c4 ud654uc7a5 uc548ud574ub3c4即使什么都不做 即使是素颜 ub10c uc544ub984ub2e4uc6cc ub208ubd80uc154你都很美丽耀眼[SungMin] ud558ub8e8uc5d0 ud55cubc88ub9cc ub110 uc0dduac01ud574 每天想你一次ub354 uc774uc0c1uc740 uc548ub3fc uc544uaef4ub458uac70uc57c爱惜的不能再爱惜了 [HeeChul] ud798ub4e4uc5c8ub358 ud558ub8e8uc758 uc36cuc0e4uc778辛苦的一天出现的sunshine uadf8ub300ub9cc uc788uc5b4uc900ub2e4uba74 O.K. uadf8uac78ub85c ub3fc身边只要你就OK了 那就可以了[LeeTeuk] ub110 ubcf4uba74 ud3b8ud574 uc774ub7f0 ub9d0 ub10c uc2ebuc5b4ud588uc9c0ub9cc 虽然你讨厌听到这样的话[ShinDong] ud589ubcf5ud574 ud558uc9c0ub9cc uc5ecuc804ud788 ub10c ubd88uc548ud574ud588uc9c0 虽然说幸福着 但仍会感到不安吧[EunHyuk] uc758uc2ecud558uc9c0ub9c8 ub110 uad34ub86dud788uc9c0ub9c8 不要怀疑 不要有困扰uc0acuc2e4 uc21cuc9c4ud55c uc0acub78cuc778uac78事实上你是多么纯真的人啊 [SiWon] uc0acub791uc2a4ub7f0 ub208 uc6c3uc74c ub118uce60 ub54c可爱的含着微笑的双眼ub10c uc544ub984ub2e4uc6cc ub208ubd80uc154你是那么的美丽耀眼[ALL] ud558ub8e8uc5d0 ud55cubc88ub9cc ub110 uc0dduac01ud574每天想你一次ub354 uc774uc0c1uc740 uc548ub3fc uc544uaef4ub458uac70uc57c爱惜到不能再爱惜 ud798ub4e4uc5c8ub358 ud558ub8e8uc758 uc36cuc0e4uc778 辛苦的一天出现的sunshineuadf8ub300ub9cc uc788uc5b4uc900ub2e4uba74 O.K. uadf8uac78ub85c ub3fc身边只要你就OK了 那就可以了[RyeoWook] oh~ uba38ub9bfuc18d uc628ud1b5 ub108uc758 uc0dduac01ubfd0Oh~ 脑海中想到的都是你[KyuHyun] ubb54uac00 ub2e4ub978 uac83uc744 uc6d0ud574ub3c4就算还想要别的什么 uc7a0uc2dc uba40ub9ac ub5a8uc5b4uc838ubd10ub3c4就算暂时别离uacb0uad6d ub108 uacb0uad6d ub108 ub108ubb34 uc2e0ube44ud574最终 最终还是你 你太神奇了[DongHae] uc7a0uc2dc ub208 uac10uace0 ub110 ub5a0uc62cub824暂时闭上眼睛 回想起你 You"re So Beautiful Girl ub108 ubfd0uc57c 你是如此美丽的女孩 只有你[YeSung] uc9c0uae08 uadf8ub300ub85c ub124 ubaa8uc2b5uc774现在你的样子毫无改变 uac00uc7a5 uc544ub984ub2e4uc6cc ub208ubd80uc154 [ub3d9ud574] My Girl依然是最美丽耀眼的 我的女孩 [ALL] ud558ub8e8uc5d0 ud55cubc88ub9cc ub110 uc0dduac01ud574每天想你一次 ub354 uc774uc0c1uc740 uc548ub3fc uc544uaef4ub458uac70uc57c 爱惜到不能再爱惜ud798ub4e4uc5c8ub358 ud558ub8e8uc758 uc36cuc0e4uc778辛苦的一天出现的sunshineuadf8ub300ub9cc uc788uc5b4uc900ub2e4uba74 O.K. uadf8uac78ub85c ub3fc身边只要你就OK了 那就可以了<

theday定冠词the,就表示有特指的一天oneday有一天，某天，常用语句首句尾aday一天，常表示花费的时间长短为一天onday没有这个说法，最多onwinterday,在冬天等用法。

a day 是特指某一天，one day 是说一天，以你的意思，应该是用 one day 吧。

daily是副词，而aday是名词，所以当你讲一句话的时候，不同的表达方式就表现出来了例子：Mydailylifeisgreat.therewasaday"slifeofmineisgreat

应该用in，in a day 在一天里。也就是在一天这段时间里，英语在一段时间里用介词 in。

天空是那种很漂亮很漂亮的灰色，漂亮得让人心疼的灰色。 行人匆匆。没有人想停下来。nobody。耳机里的声音是： Ever close your eyes Ever stop and listen Ever feel alive And you"ve nothong missing You don"t need a reason Let the day go on and on Everwhere around you Give into it now Let the day surround You don"t need a reason Let the rain go on and on Enya安静的声音，这首歌是。可是现在的我是阴天。 我把耳机的声音开到最大。震耳欲聋。然后，目空一切地向前走着。一直地走。当我想停下来的时候，却发现，我迷失在这个城市的边缘。我找不到自己了。我的信仰，找不到了。我开始在边缘游走着。我在寻找，我留下了一些什么。但是，什么也没有，只有一大片一大片的灰色。脸上被某种冰凉液体弄得湿湿的。我以为是泪水，可是我的眼睛是干涩的，像一片干枯的湖。抬头仰望，下雨了。Rain is god"s tears,雨是上帝的眼泪。雨水毫不顾忌地洒落下来，冰冷的感觉，冷却了我的一切。心仿佛在一瞬间堕落了。天空乱七八糟地黑作一团，我浑身都湿透了，全然不顾周围的一切。忽然有一种很咸的液体顺着我的喉咙一直流向我的心脏。心开始变暖了。 我的世界变了。

我的春节(My Spring Festival)My Spring Festival is special. My uncle and my aunt came back from Shanghai. My family were very happy to keep the Spring Festival with them. And it was the most exciting festival of all the festivals. On New Year"s Eve, my father and my uncle talked about their work together. My mum did some cooking with my aunt Grandparents and I watched the New Year TV programmes. At about six o"clock, we had a special family dinner. We all thought the dumplings were delicious. On the first day of the New Year, we visited our relatives. In the afternoon, we went shopping in Jiefanf Road. My uncle bought some Jay"s CDs. He likes Jay"s music very much. There were so many people on the road. It was more alive than any other time of a year. On the second and the third days, we spent a wonderful weekend in the country. There were much bigger trees than in the city. And the animals were more beautiful than in the city. We all enjoyed ourselves. -

你好： 不定冠词的基本用法有：（1） 不定冠词有a和an两种：a用于辅音音素开头的词前，an用于元音音素开头的词前。例如：a boy, a city, a girl, a useful animal , an old man, an honest boy,a dog.（2） 用来表示“—”的意思，但不强调数的观念，只说明名词为不特定者。即不具体说明是何人何物。例如： A woman is looking for you. We work six days a week. （3）不定冠词含有“—”的意思，但数量观念没有one强烈，在句子里边一般可以不必译出，但若有“一个”的意思则译出，例如： —— An egg is good for you. 蛋对你有好处。 —— How much is it ? 多少钱？ ——six yuan a kilo. 六元一公斤。 （4）一般用在可数名词单数前，指人或事物的某一种类。例如： Bill is a student. Pass me an apple, please.（5）一般a day 在做主语时放在首位，其余可以放在任何地方，大都在末尾。希望我的回答对你有所帮助，祝你天天开心！

不是还是一天的意思每天是day by day

Last Sunday,I had a great time.I went to the countryside with my family.I had never seen such blue sky. The air is fresh and there are lots of beautiful flowers.We had a picnic there,and then we went fishing 、went camping and fle kites.We talked 、played and laughed. All the thing we could see is just happiness.We took a lot of photos to remember the happy day.What a wonderful day

a day是指不确定的某一天，一般也很少这么说，一般都说ONE DAYevery day是指每一天，并且有强调每一之意。

one day 和a day 在针对“一天”来说几乎相同. one day 也可指过去的某天,或将来的某天. e.g. One day,.(好多故事都这么开篇吧)

在从句里如果做宾语或主语就用which;如果做状语就用when例子：ThatisadaywhichIwillrememberforever.（在从句里做宾语）Thatisadaywhenitrains.(做状语)

a day 意思是一天the day是特指的那一天唯独不能用an，an后面只能跟第一个音发元音的单数单词

　　A happy day　　Today, I got up very early, I had a very good breakfast, then I went out to play with my friend, We had a very good time. In the afternoon, I went swimming with my father, it was very hot, but we felt very good in the water. After supper I began to do my homework, I didn"t think it is difficult, so I finished it very early.Then I read some books and went to bed..Yestaday,i went to the zoo,and i really had a happy day.　　In the zoo,i saw lovely pandas which are the special animal that only live in china.There are also many other animals that interested me very much.　　...I spent nearly a whole day in the zoo,although i was tired ,i was really happy.　　...How happy a day i had.　　快乐的一天　　今天，我很早就起床了，我有一个非常好的早餐，然后我去外面和朋友玩，我们有一个很好的时间。当天下午，我就跟着爸爸游泳，这是非常热的，但我们在水里感觉非常好。晚饭我开始做我的功课后，我不认为这是困难的，所以我完成了它很早，然后我读了一些书，然后去睡觉.. 昨天我去了动物园，我真的有一个幸福的天。　　在动物园里，我看到了可爱的大熊猫哪些是特殊的动物，只生活在我们国家.那里也有我感兴趣的很许多其他动物。 　　...我在动物园花了将近一整天的时间，虽然我累了，我真的很开心。　　...如何快乐的一天我有。

这是一句谚语，An apple a day keeps the doctor away. 一天一苹果，疾病远离我。意思就是苹果富含营养有益于身体健康，每天吃个苹果就不容易生病。百度嫌我字数不够

students have having tutors at the weekend.There are two different viewpoint about it.Some people think it is necessary to have a tutor.Studying with a tutor is much better than studying by students themselves.It is a good way for students to review the knowledge which they learnt in class. They also can learn more things from the tutor.On the contray, some paople believe that it is not necessary to have a tutor.Students may depend on the tutor,they don"t study by themselves,it will makes them have a bad behaviour of study.Otherwise, students need to have a rest on the weekend.Some tutors only want to earn money,they don"t pay much attention to the students"s study. In my opinion, I think it is better for students to have a tutor. It is really helpful for students.They can learn things more quickly,

what a day！多开心的一天！多糟糕的一天！双语对照例句:1.What a day for all of us who looked on fearfully, hopelessly, andmournfully. 我们恐惧地、绝望地、悲伤地目击了整个过程，这是怎样的一天啊。2.What a day for it, huh? 今天的天气多适合啊恩

您好！习惯和语法上不能这样用。事实上，An apple a day keeps doctor away.(一天一苹果不劳医生开药方。)这是一个俗语。而且，语法上来说，an apple a day 是 eat an apple each day(每天吃一个苹果的意思。)所以，语序不能颠倒。谢谢！希望帮助到您!

a fine day This morning,i got a call from my foreign friend Jack,he said he had reached the airport and had me meet him there,at which i felt surprised.not only did we talk about the difference and diversity of American and Chinese culture,but we also elaborated our interests to each other on our way home. Hardly had we got home,we smelt something that seemed scrumptious,in effect,my mother has arranged a good meal for Jack"s coming.After our supper,i took Jack to visit some resorts of my hometown,which gave him insights into what"s chinese culture,we talked about a lot on what we saw.Obviously,speaking with him helped me a lot with my oral English. As is known to all,everybody can enjoy a golden time in his or her life,no matter how long it is,it can bring us a great deal of fun,today is my golden one!

what a day根据不同的语境可译为多好的一天；多糟糕的一天。重点词汇解释：1、whatdet. 什么；多么；多少pron. 什么；多么；多少adj. 什么；多么；何等adv. 到什么程度，在哪一方面int. 什么；多么双语例句：What do you want？你要什么？2、dayn. 一天；时期；白昼adv. 每天；经常在白天地adj. 日间的；逐日的双语例句：And it has snowed almost every day for the past week.而且过去的一周几乎每天都在下雪。day的用法：day的基本意思是一天，指二十四小时长的一段时间，是可数名词。也可指日间，白天，既可用作可数名词，又可用作不可数名词，通常不加冠词。day也可表示工作日，指一天二十四小时之内的工作时间，是可数名词。day接双宾语时，间接宾语是人，双宾语的句型可以转变为跟to短语的句型。day还可作时期，时代，寿命的意思，常用复数形式，若用单数常须与my，their等物主代词连用。

　　每天学习英语，每天起来读英语，这样我们的英语还没有进步一定是方法没把握对。下面是我给大家整理的每天的英语怎么写，供大家参阅! 　　每天的英语怎么写 　　英 [u02c8evrideu026a] 美 [u02c8u025bvriu02c8de] 　　everyday 　　adj. 日常的，平常的; 普通的; 每天的; 经常; 　　每天的英语例句 　　1. Daily facial exercises help her to retain the skin"s elasticity. 　　每天做面部运动帮助她保持皮肤弹性。 　　2. Someone comes in every day to check all is in order. 　　每天都有人来检查是否一切都井然有序。 　　3. Be sure you get your daily quota of calcium. 　　要确保每天的钙摄入量。 　　4. Try to eat at least four slices of bread a day. 　　每天尽量至少吃4片面包。 　　5. You should wash your feet and your privates every day. 　　应该每天洗脚，并清洗阴部。 　　6. More than six million youngsters tune in to Blockbusters every day. 　　每天有600多万年轻人收看“热门大片”这档节目。 　　7. I wear my old shoes every day. One sole has come unglued. 　　我每天都穿那双旧鞋，有一只鞋底已经脱胶了。 　　8. You"re quite a party animal aren"t you, out there every night. 　　你就是为派对而生的，不是吗，每天晚上你都去参加派对。 　　9. I felt like I was being kicked in the teeth every day. 　　我觉得每天都在遭受失望的打击。 　　10. Bank robberies, burglaries and muggings are reported almost daily in the press. 　　报纸上几乎每天都有抢劫银行、入室行窃和拦路抢劫的报道。 　　11. A surprising number of customers order the same sandwich every day. 　　每天点同一种三明治的顾客多得惊人。 　　12. The mixture can be used as a gargle several times a day. 　　每天可用这种混合液漱几次口。 　　13. Every day of sunshine strengthens the feelings of optimism. 　　每天晒太阳让人心情更加开朗。 　　14. Normally, the transportation system in Paris carries 950,000 passengers a day. 　　正常情况下，巴黎的交通系统每天运送95万乘客。 　　15. They go for decorous walks every day in parks with their nanny. 　　他们每天都和保姆一起在公园里散步，表现得很有教养。 　　everyday的双语例句 　　1. One in five young adults was struggling with everyday mathematics. 　　1/5的年轻人做日常的数学计算都费劲。 　　2. The film chronicles the everyday doings of a group of London schoolchildren. 　　电影记载了一群伦敦小学生的日常活动。 　　3. The series chronicles the everyday adventures of two eternal bachelors. 　　这个系列剧按照时间顺序记述了两个老光棍每天的奇遇。 　　4. No matter what happens to us in the future, everyday we are together is the greatest day of my life. I will always be yours. 　　无论未来何去何从，我们在一起的每一天都是我人生中最为辉煌的日子。我永远属于你。 　　5. Many of the differences in everyday life remain. 　　日常生活中的许多差异仍然存在。 　　6. The Internet has become part of everyday life . 　　互联网已成为日常生活的一部分。 　　7. She watches television to relieve the monotony of everyday life. 　　她天天靠看电视来解闷儿。 　　8. everyday objects such as cups and saucers 　　诸如杯碟之类的日用品 　　9. the synthesis of art with everyday life 　　艺术与日常生活的结合 　　10. She longed for something to relieve the tedium of everyday life. 　　她渴望有什么事情能排解她日常生活中的烦闷。 　　11. They sought solace in religion from the harshness of their everyday lives. 　　他们日常生活很艰难,就在宗教中寻求安慰. 　　12. My necklace has a heart pendant, but I don"t wear it everyday. 　　我的项链有一个心形的垂饰, 但我并非每天都戴他. 　　13. In everyday life you may sometimes have a brush with other people. 　　在日常生活中,你有时会与别人有点小摩擦. 　　14. The safety net is an image commonly employed in everyday life. 　　安全网是日常生活中经常用到的一个比喻. 　　15. Their lives consist of the humdrum activities of everyday existence. 　　他们的生活由日常生存的平凡活动所构成. 　　

这个短语的意思是一天一夜。“一天”这个词有两个含义，在和“一夜”并用时只表示白天，在单独使用时则表示一天一夜。你题中的两个“一天”都是和“一夜”并用，所以都只表示白天12小时。

每天用苹果，博士学位远离我

After three days 三天以后Before three days 三天以前

my day, 因为my 已经起到一个定语的作用，所以不再需要定冠词和不定冠词来修饰了。如果要表达出一个的话，只能是 one of my days比如 我的一个漂亮的女孩是 my beautiful girl 不会是 my a beautiful girl 或者 the my beautiful girl

Oneaday是拜耳公司的一款维生素。德国拜耳是国际上值得信赖的保健品生产商，Oneaday是它的一款主流产品，分男用和女用。成分:碳酸钙、镁氧化物、钾氯化物、纤维素、酸、dl- 阿尔发的 Tocopheryl 醋酸钠、Gelatin 、钠，洋槐、磷酸盐、氧化锌、硬脂的酸、矽二氧化物、糊精、镁硬脂酸盐、玉黍蜀淀粉、锰硫酸盐、钙矽酸盐、蔗糖、二价铜的氧化物、树脂、葡萄糖、核黄素、维他命醋酸盐、维生素 D等。用法：每天一粒，随餐服用。注意：室温储存，避免小孩接触，避免高温。扩展资料：1、拜耳公司是世界最为知名的世界500强企业之一。公司的总部位于德国的勒沃库森，在六大洲的200个地点建有750家生产厂；拥有120,000名员工及350家分支机构，几乎遍布世界各国。高分子、医药保健、化工以及农业是公司的四大支柱产业。2、公司的产品种类超过10，000种，是德国最大的产业集团。该公司生产的阿司匹林，被人们称为“世纪之药”，也创造出了“魔鬼的杰作”，就是海洛因。3、拜耳十字是拜耳公司的标志，1904年起开始使用。拜耳十字由横排和竖排的“拜耳”（BAYER）英文单字组成，两个词共用一个“Y”字母，最外面为一个圆圈。拜耳总部在勒沃库森有一个大的霓虹灯标志。这个1958年安装的拜耳十字是世界上最大的霓虹灯广告。参考资料：百度百科：拜耳公司

A day 的意思：一天例句：1.An apple a day keeps the doctor away 一天一个苹果医生将会远离。2.Everyone should brush at least twice a day. 每个人每天至少要刷两次牙。3.He spends an hour a day on his business. 他每天花一个小时在他的生意。4.You should take a day off tomorrow. 你明天应该体息一天。5.Termites eat 24 hours a day. 白蚁一天24小时都在吃。

one day既有一天的意思，又有某天的意思。a day只有一天的意思，one day和a day在针对“一天”来说几乎相同。one day也可指过去的某天或将来的某天。one day的用法one day与some day均可用作状语，表示“有一天”，但两者所连用句子时态稍有区别：1、one day可指过去或将来，即可用于过去时态或将来时态。如：One day the temperature was 30℃. 有一天温度达到30摄氏度。I will [am going to] climb that mountain one day. 总有一天我要爬那座山。One day people will be able to go to the moon on holiday. 总有一天人们可以到月球上去度假。2、some day通常只指将来，即只用于将来时态。如：We"re all going to be old some day. 总有一天我们都会老的。Some day I"ll come back and marry her. 总有一天我要回来娶她。注：有时虽然不是将来时态，但句子意思表示的是将来意义。如：You"re sure to regret one day. 你准有一天会后悔。I want to get married one day. But before that, I want to travel. 总有一天我要结婚。但在那之前，我要旅游。另外，在特定语境中some day有时可指过去将来。如：I never realized that some day I would be living in China. 我从未想到将来有一天会在中国居住。

a day 指一天 one day也有指一天的意思,还可以解释为：过去某天或将来某天 some days指将来某些日子 on a day是说在某一天

你要区分a和one.a是不定范围限定词。是从范围上限定名词。one是定量数量限定词。是从数量上限定名词。aday的含义是某一天做状语通常会是这样：onceaday,severaltimesaday.oneday的含义是一天。作状语可表示时间长度。

区别在于 每一天 和 一天

a day 指一天 one day也有指一天的意思,还可以解释为：过去某天或将来某天 some days指将来某些日子 on a day是说在某一天

Everyday作形容词，表示每天的，或日常的，或平凡的，例如： This is a matter of everyday occurrence. 这只是一件普通小事（平常事）。 至於every day，则十分简单，表示每一天，例如： She goes to school every day. 她天天上学。 有些人要加强语气，常在every和day之间加上single，例如： She comes to see us every single day. 她每天都来看我们。a day是一天……，从中文就可以区别

从对比的角度分析下：Alltheday=thewholeday一整天someday（将来的）某一天相对的是 oneday(过去的）某一天 allday:一般指一整天，包括白天和晚上 alltheday一般指一天，单只白天其实在实际应用中，两者的区分度不高Alladay:这里all一般是句子其它成分的同位语的. all在这里跟aday没有直接的搭配关系比如：Ihopeyouallhaveawonderfulday.我希望你有快乐的一天。all在句子是做you的主语同位语，同aday没有直接的搭配关系另外关于all和whole的区别1）all/whole都可以与可数名次搭配alltheday=thewholeday 2)all可以同不可数名词搭配，但是whole不可以shehasdrunkallthewater.3)whole修饰抽象名词，但是all不可以Icantellyouthewholetruth.Br:希望对你useful.

不是 还是一天的意思 每天是day by day

twice a day一天两次双语对照词典结果：twice a day[英][twais u0259 dei][美][twau026as e de][医]一天二次; 以上结果来自金山词霸例句:1.Process email only twice a day. 一天只登陆两次你的邮箱。.___________________________很高兴为你解答！如有不懂，请追问。 谢谢！

a day表一天中的频率。举例：I read books three times a day.(我一天读三次书）every day表每天都做，频率是每天。举例： I play basketball every day. （我每天都打篮球）

a day是指一天，every day是指每天

加介词on天的前面加介词on，时间的前面加介词at，如onmonday,at9:00不懂得随时问，希望可以帮到你

Today is a fine day.And I am very lucky. In the morning,I"m go fishing in a river with my parents.As time goes by,I am fishing a big fish.I am very happy,but my parents have no one fish.Next,I am fishing a small fish,but I still happy.Because my parents still have no one fish.It"s time to go home,I am fishing ten fishs,but my parents are only fishing a small fish.In the afternoon,I am playing football with my buddies.MingMing has the ball,he is kicking it to me.I am kicking the ball.It"s a beautiful goal.Next,PingPing has the ball,he is kicking to Mike.Now,Mike has the ball,he is kicking it.It"s a goal.Now,we are winning. Today I am very lucky.And I am so happy.

一天苹果，医生远离我。这是英语的一句谚语，已经成为固定表达。An apple a day keeps the doctor away. 主语an apple , a day 定语，keeps 谓语，the doctor 宾语，away 副词作宾语补足语。

on表在某天，如,onadaywhenit"scloudless或onadaywhenI"mnotbusy.Inaday表一天时间，如Romeisnotbuiltinaday.又如LasVegasinaDay一般宣传语时表"拉斯维加斯一日游"(以一天的时间)