0910AW SPECTACULAR 之【SU & SY SO】第二十五期——A versus An

草木也知愁UID: 2487572

Articles: A versus An

This resource was written by Purdue OWL.
Last full revision by Chris Berry.
Last edited by Allen Brizee on January 22nd 2008 at 3:27PM
Summary: This short handout deals with which article to use before a noun -- "a" or "an."

Articles: A versus An

How do you know when to use the indefinite articles?

"A" goes before all words that begin with consonants.
·a cat
·a dog
·a purple onion
·a buffalo
·a big apple

With one exception: Use "an" before unsounded h.
·an honorable peace
·an honest error

"An" goes before all words that begin with vowels:
·an apricot
·an egg
·an Indian
·an orbit
·an uprising

With two exceptions: When u makes the same sound as the y in you, or o makes the same sound as w in won, then a is used.
·a union
·a united front
·a unicorn
·a used napkin
·a U.S. ship
·a one-legged man

Note: The choice of article is actually based upon the phonetic (sound) quality of the first letter in a word, not on the orthographic (written) representation of the letter. If the first letter makes a vowel-type sound, you use "an"; if the first letter would make a consonant-type sound, you use "a." So, if you consider the rule from a phonetic perspective, there aren't any exceptions. Since the 'h' hasn't any phonetic representation, no audible sound, in the first exception, the sound that follows the article is a vowel; consequently, 'an' is used. In the second exception, the word-initial 'y' sound (unicorn) is actually a glide [j] phonetically, which has consonantal properties; consequently, it is treated as a consonant, requiring 'a'.

草木也知愁UID: 2487572

update

rushtosummerUID: 2735551

Rushtosummer的学习笔记（25）A versus An
How do you know when to use the indefinite articles?
"A" goes before all words that begin with consonants.
With one exception: Use "an" before unsounded h.
an honorable peace
an honest error
"An" goes before all words that begin with vowels:
With two exceptions: When u makes the same sound as the y in you, or o makes the same sound as w in won, then a is used.
a union
a united front
a unicorn
a used napkin
a U.S. ship
a one-legged man
Note: The choice of article is actually based upon the phonetic (sound) quality of the first letter in a word, not on the orthographic (written) representation of the letter.

小灵易碎UID: 2733622

小灵的学习笔记
With one exception: Use "an" before unsounded h.
·an honorable peace
·an honest error

With two exceptions: When u makes the same sound as the y in you, or o makes the same sound as w in won, then a is used.
·a union
·a united front
·a unicorn
·a used napkin
·a U.S. ship
·a one-legged man

Note: The choice of article is actually based upon the phonetic (sound) quality of the first letter in a word, not on the orthographic (written) representation of the letter. If the first letter makes a vowel-type sound, you use "an"; if the first letter would make a consonant-type sound, you use "a." So, if you consider the rule from a phonetic perspective, there aren't any exceptions. Since the 'h' hasn't any phonetic representation, no audible sound, in the first exception, the sound that follows the article is a vowel; consequently, 'an' is used. In the second exception, the word-initial 'y' sound (unicorn) is actually a glide [j] phonetically, which has consonantal properties; consequently, it is treated as a consonant, requiring 'a'.
总结起来就是元音音标前用an,辅音音标前用a