UN. USA. ATM. WTO. FBI. CPU.
What do these all have in common? They are acronyms: a type of abbreviation made up of the initial letters of a phrase. Some acronyms are pronounced as they are read, such as NATO (/neto/), which is short for the North Atlantic Treaty Organization. Some are pronounced letter-by-letter, such as FBI, which is the acronym for the Federal Bureau of Investigation.
How do you know which acronyms are pronounced like they are read (NATO) and which ones are letter-by-letter (FBI)? One hint is whether the consonant cluster exists in English. There is no English consonant cluster /fb/, so the only choice is to pronounce FBI by each letter: F - B - I.
Don't rely solely on that tip. In theory, USA could be pronounced as it is read. But we all know it's pronounced U - S - A.
Here's the good news. Once you know that an acronym has a letter-by-letter pronunciation, there is a simple rule for knowing which letter receives the stress: It is always the last letter. Well ... I should say almost always. This is English we are talking about, where exceptions to the rule are a given.
Where can you get cash? At an A - T - M
Where can you find a diplomat? At the U - N
Where is the UN? In the U - S - A
Want to practice? Take a look at this acronym list and see if you can determine which ones are pronounced as they are read and which ones are pronounced letter-by-letter. Remember, if you get one wrong, it is ok to LOL at yourself!