Here's why:
* The vowel "i" in "pine" is short. It has a short "i" sound, similar to the "i" in "pin" or "tin".
* Long vowel sounds are typically associated with a vowel followed by a silent "e" at the end of a word. For example, "pine" would be "pine" if it had a long vowel sound.
Therefore, "pine" has a short vowel sound.