“A” vs. “An” in writing vs. pronunciation
In an article in The Economist, it is written "That was raised in an FT op-ed...". Why is it "an FT op-ed" and not "a FT op-ed"?
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An abbreviation or initialism takes the article appropriate to its pronunciation. The author intends it to be said "eff-tee," so it takes the "an" rather than the "a."
The choice of a/an depends on how the subsequent word is pronounced, not how it is spelled. FT is pronounced "ef tee" [ɛf ti]; it begins with a vowel sound, and therefore the correct article is "an".