Ron's ESL Blogs

There are five vowel letters: a, e, i, o, u among 26 English letters. When we talk about the differences between “a” and “an”,  we say that “a” is used before a consonant and “an” is used before a vowel. But ESL students often make the following mistakes in their writing:

- an university (X)

- a hour (X)

- a SUV (X)

- an one-time password (X)

- an unit (X)

- an European (X)

- a honor (X)

Why do students make these mistakes? Because they misunderstand their teachers. “An” is used before a vowel sound, not just a vowel letter. “U” is a vowel letter, but it has two pronunciations. When it is pronounced as a vowel sound, we use “an,” such as “an uncle,” “an umbrella,” but “a uniform,” “a university” because “u” in these two words is pronounced as a consonant.

“H” is sometimes not pronounced in an English word, such as “hour,” and “honor.” Since “h” is not pronounced, both words start with vowel sounds. So we should say “an hour” and “an honor.” In the words “hotel” and “half,” “h” is pronounced, so we say “a hotel” and “a half.”

“European” starts with a vowel letter “e,” but it is not pronounced as a vowel sound. So you need to say “a European.” It’s the same reason for “one-time.” It starts with the vowel letter “o,” but the letter is not pronounced as a vowel sound. So we should say “a one-time password.” We say “an SUV” because it starts with a vowel sound, although “S” is a consonant letter      – Ron Lee