* The vowel sound in "humor" is a short "u" sound, as in "cup" or "duck".
* Long vowel sounds are typically associated with vowels that are pronounced as their letter name. For example, "long a" sounds like "a" in "cake," "long e" sounds like "e" in "see," etc.
So, while "humor" has the letter "u," its vowel sound is short, not long.