Here's why:
* They are not "long" in the traditional sense: Unlike long vowels, R-controlled vowels don't create a sustained sound. They don't have the same "stretched out" quality as vowels like "ee" or "oo."
* They are not "short" in the traditional sense: They have a more complex sound than typical short vowels. They don't sound like "ah" or "eh" for example.
Instead, R-controlled vowels have a distinct sound influenced by the presence of the letter "r":
* They are often described as "mid-range" in length.
* They have a different quality from both long and short vowels.
* They can be considered a separate category of vowel sounds.
Here are some examples:
* "car" - The "ar" sound isn't like the "a" in "cat" (short) or the "a" in "cake" (long). It's a unique sound.
* "bird" - The "ir" sound isn't like the "i" in "bit" (short) or the "i" in "bike" (long).
So, while R-controlled vowels don't fit neatly into the "long" or "short" categories, they have their own unique qualities and characteristics.