You learned: "a" before a consonant, "an" before a vowel. So you say "a hospital, a house, a horse". Then you read "an hour" and panic - the word starts with H!
Here is the rule: The choice between "a" and "an" depends on the SOUND of the next word, not the spelling. If the H is silent, the next sound is a vowel, so use "an".
The Core Rule
"A" is used before a consonant sound. "An" makes pronunciation easier before a vowel sound by inserting an N to avoid two vowels colliding. Silent H means the word starts with a vowel sound, so it gets "an".
| Word | Article | Why |
|---|---|---|
| hour | an hour | Silent H → starts with /aʊr/ (vowel) |
| honest | an honest mistake | Silent H → starts with /ɑn/ (vowel) |
| honor | an honor | Silent H → starts with /ɑn/ (vowel) |
| heir | an heir to the throne | Silent H → starts with /ɛr/ (vowel) |
| house | a house | H is pronounced → consonant sound |
| hospital | a hospital | H is pronounced → consonant sound |
The Silent-H Word List
These are the main English words with a silent H. Memorize them and you have the full rule:
- hour /aʊr/ → an hour, an hourly rate
- honest /ˈɑnəst/ → an honest answer, an honestly great show
- honor / honour /ˈɑnər/ → an honor, an honorable choice, an honored guest
- heir / heiress /ɛr / ˈɛrəs/ → an heir, an heiress to the fortune
The H stays silent in all derived forms. So "honesty, honorable, hourly, heirloom" all take "an".
Practice the Most Common Pairs
The Bigger Principle: Sound, Not Spelling
The rule applies to MANY situations. The article follows your ears, not your eyes:
| Tricky case | Article | Why |
|---|---|---|
| a university | a | starts with /j/ sound (you-ni) |
| a European | a | starts with /j/ sound (you-ro) |
| a one-way street | a | starts with /w/ sound (won-way) |
| an MBA | an | letter M starts with /ɛ/ sound |
| an FBI agent | an | letter F starts with /ɛ/ sound |
| an X-ray | an | letter X starts with /ɛ/ sound |
| a UFO | a | letter U starts with /j/ sound |
The Old "An Historic" Tradition
You may see phrases like "an historic moment" or "an hotel" in older books. In old British English, the H was sometimes weakly pronounced or dropped after an unstressed syllable, so people used "an". This is now considered old-fashioned in both British and American English. Modern rule: use "a historic, a hotel, a horrific" because the H is fully pronounced.
The Reduction in Speech
In fast speech, "a" reduces to /ə/ (schwa, like the "uh" in "sofa"). "An" reduces to /ən/. The /n/ exists only to bridge two vowels - it is purely mechanical.
- "a book" → /ə bʊk/ "uh book"
- "an apple" → /ən ˈæpəl/ "un-apple" (the N links to the next word)
If you say "a apple" (without the N), your tongue has to stop awkwardly between two vowels. The N solves the problem. That is the entire point of the rule.
Test Yourself
Choose A or AN for these:
- __ honest opinion
- __ historic event
- __ hour and __ half
- __ honorary degree
- __ university student
- __ FBI agent
- __ one-time offer
- __ heir to the throne
Answers: an, a, an / a, an, a, an, a, an.
One Quick Drill
"It was AN honor to spend AN hour with AN honest man. He was AN heir to AN historic family but worked at A hotel near A university for A modest salary."
Read it twice. The article follows the SOUND. That one habit makes your English noticeably more accurate.