What is the rule for the use of "a or an" when using this sentence: My father is "a/an" M.D. I never know what to use because M is not a vowel but it sounds like one. I use "an" because it sounds better to me, to my knowledge, I've never heard a rule for this .
Could you please give me some guidence on this? Thank you, M.K. Eastman
Top answer
Sure, there's a rule. The a/an decision is based on how it sounds, not what the letter is. An em-dee.
— BarbaraPA
Sure, there's a rule.
The a/an decision is based on how it sounds, not what the letter is.
An em-dee.
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One should use "an" M.D. because the choice is not determined by whether the article precedes a consonant or a vowel but by whether it precedes a vowel SOUND or a consonant SOUND. In this case one is not pronouncing a word that begins with M but rather the name of the letter M and it is "em," thus beginning with a vowel sound. For example "a university" because the sound is "yu." RB