Listen to the word immediately after the gap. Choosing a or an depends on its opening sound. Read the whole phrase aloud before selecting an article, rather than relying only on the first written letter.
Check what the noun means here
Begin with a single countable thing that is not a particular one already identified, such as a book or an apple. The article the can identify something specific; that choice needs its own context.
Do not put a/an directly before plural nouns or ordinary uncountable uses: a book works, but a books does not. We do not normally use a water for water as a substance.
Listen to the opening sound
Use a before a consonant sound and an before a vowel sound. A book and an apple make useful starting examples.
When an adjective comes before the noun, listen to that adjective: a red apple, an old bag. As an extension, compare a university, which begins with a sound like you, and an hour, whose h is silent. A beginner does not need to memorise a long exception list.
Worked example: packing a schoolbag
These separately written sentences show why changing the word after the article can change the choice. Read each phrase as a whole.
Read the phrase, then choose
Say the phrase after the gap aloud. Choose a or an and identify the word whose opening sound matters.
Try it yourself
Use a or an. Each sentence introduces one ordinary object.
- I have ___ pencil.
- There is ___ orange in the box.
- Ben carries ___ old schoolbag.
Show an explained answer
- A pencil: pencil begins with a consonant sound.
- An orange: orange begins with a vowel sound.
- An old schoolbag: old immediately follows the article, so its vowel sound matters.
