2016-12-20
作者：GoldenDict
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前天发出《美国小朋友用什么词典？ 》一文后，有前辈赠送了几部词典，其中一部是 1986 年版 Houghton Mifflin Intermediate Dictionary 。Houghton Mifflin 就是大名鼎鼎的 American Heritage Dictionary 的出版商。
词典的第一个词条，当然就是 a ，如图： 
a 做不定冠词（indefinite article），不知道这点的英语学习者几乎没有，但是，a 作介词（preposition）？ r u kidding? ::Houghton Mifflin Intermediate Dictionary, 1986 preposition
In or to each; per:
We paid five dollars a person for ther tickets.
An apple a day keeps the doctor away.
有问题，查词典。六大高阶英语学习词典都没有给 a 标注“介词”词性，不过 OALD、MWALD 注明在特定义项， a = per ，而 per 只有介词词性，详情如下。
::OALD indefinite article
used when talking about prices, quantities and rates （用于价格、数量、比率等）一，每一 SYN per
• They cost 50p a kilo. 其价钱是一公斤 50 便士。
• I can type 50 words a minute. 我每分钟能打 50 个单词。
• He was driving at 50 miles an hour. 当时他正以每小时 50 英里的速度驾车。
::LDOCE indefinite article, determiner
used to mean ‘each’ when stating prices, rates, or speeds每一（个）〔用于表明价格、比率或速度〕:
• I get paid once a month. 我的工资一个月发一次。
• The eggs cost $2 a dozen. 鸡蛋两美元一打。
::CALD determiner
used when saying how much someone earns or how much something costs in a certain period （指特定时间段内的收入或费用）一，每
• She earns $100 000 a year.她一年挣10万美元。
• My plumber charges £20 an hour.管子工每小时收我20英镑的维修费。
• I pay £5 a week for my parking permit.我的停车费是每周5英镑。
::MED determiner
used in phrases showing how much something costs, how often it happens, how fast it goes etc 一，每（用于表示某事物的花费、频率、速度等的短语中）
• Meetings are held four times a year (=four times every year). 会议每年举行4次。
• tomatoes at £1.20 a kilo (=each kilo costs £1.20) 每公斤1.2英镑的西红柿
• The car was travelling at 90 miles an hour. 那辆轿车在以每小时90英里的速度行驶。
::COBUILD DET 限定词
（用于表示比率的短语中）每一 You use a or an in expressions such as eight hours a day to express a rate or ratio.
【搭配模式】：num DET sing-n
• Prices start at £13.95 a metre for printed cotton… 印花棉布以每米13.95英镑的价格起售。
• The helicopter can zip along at about 150 kilometres an hour. 该直升机能以每小时150公里左右的速度疾进。
::MWALD indefinite article
used in phrases that describe how often something occurs, how fast something is going, etc.
• They meet twice a week. [=twice each week]
• The car was traveling at a hundred miles an [=per] hour.
不过母语词典，尤其是大型美语词典，则都是标注了的。
::Merriam-Webster Collegiate Dictionary preposition
Etymology: Middle English, from Old English a-, an, on
Date: before 12th century
1 chiefly dialect : on, in, at
2 : in, to, or for each
twice a week
five dollars a dozen
::Merriam-Webster Unabridged Dictionary prep.
: in, to, or for each : for every — used before words with an initial consonant sound
twice a week
two dollars a pound
::Webster’s New World College Dictionary prep.
[< OE an, on, in, on, at]
to each; in each; for each; per [once a day]
::Random House Webster’s Unabridged Dictionary prep.
each; every; per: ten cents a sheet; three times a day.
::American Heritage Dictionary prep.
In every; to each; per:
once a month; one dollar a pound.
再回到最开始的例句。
::剑桥高阶英汉双解学习词典 An apple a day keeps the doctor away.
■ This means that eating an apple each day can help to keep you healthy. 一天一苹果，不用上诊所。
这里的 a 究竟是不定冠词，还是介词，人微言轻，我没有任何观点，只是觉得把 a 看作和 per 等价的介词，很容易从语法上理解， a day 作为介词短语后置修饰 apple ，不得不说美国的语法学家、词典编纂者真的是实用主义至上。
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发表于 2017-9-13 23:23