How do vowels differ from consonants?

Vowels can be spoken indefinitely because they are produced with an open vocal tract, allowing for sustained sound without blockage. This unrestricted airflow enables the speaker to hold the vowel sound for an extended period, making it possible to emphasize or elongate these sounds in speech. For instance, when saying the letter "A" in a prolonged manner, it remains clear and consistent throughout its duration.

In contrast, consonants typically require some form of closure or constriction in the vocal tract, which limits their ability to be extended in the same way. As a result, this essential quality of vowels showcases a key distinction between the two types of sounds, emphasizing the unique characteristics of vowel pronunciation.