Here's why:
* Short vowel sounds are typically quick and sharp, often represented by a single letter in the spelling (like "i" in "lion").
* Long vowel sounds are usually drawn out and can be represented by a single vowel letter followed by a silent "e" or a double vowel (like "i" in "kite" or "pie").
The "i" in "lion" is a short vowel sound, as it's quick and sharp, and the "o" is silent.