Here's why:
* Short vowel sounds are typically quick and sharp. In "DATE", the "A" makes a short, sharp sound, similar to the "a" in "cat" or "hat".
* Long vowel sounds are typically drawn out and can often be represented by a single vowel letter followed by a silent "e" at the end of a word. This is not the case with "DATE".
Therefore, the vowel sound in "DATE" is short.