Here's why:
* The vowel sound in "cavity" is a long "a" sound. This is similar to the "a" sound in "fate" or "day".
* Short vowel sounds are typically found in words where the vowel is followed by a single consonant, like "cat", "bed", or "hop". In "cavity", the "a" is followed by a consonant cluster ("v-t-y").
Let me know if you have any other words you'd like to analyze!