Uso de a , an e one

 

“A” and “An”

Use:
“A” and “an” are indefinite articles.
They mean “one” in a general sense — you use them when you talk about something non-specific or mention it for the first time.

Use “a” before a consonant sound:

• a cat

• a book

• a university (“university” starts with a “ju” sound → consonant sound)

Use “an” before a vowel sound:

• an apple

• an hour (the “h” is silent, so it starts with a vowel sound)

• an umbrella

It’s about sound, not spelling!
For example:

• a house → “h” is pronounced → consonant sound

• an honest man → “h” is silent → vowel sound

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“One”

Use:
“One” is the number 1.
Use it when you want to emphasize that you mean exactly one, not two or three.

Examples:

• I have one brother. (I don’t have two or three — just one.)

• Give me one apple, please.

• Not two, just one!

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