Rules for using articles "a" and "an"

• When choosing an article a/an, pay attention to the SOUNDS (not letters) the words start with (a + a consonant sound, an + a vowel sound).
• Vowel sounds are /a/, /e/, /i/, /o/, /u/.
• All the others (e.g. /b/, /t/, /k/,/n/, /j/, /w/...) are consonant sounds.