By sound, most long vowels say their names (A, E, I, O, and OO/YOO). Often a long vowel will precede a consonant-E (silent E) at the end of a word (came, late, note) but there are several exceptions (give, have, come, some).
The word "humanity" has a long vowel sound, which means the first vowel "u" is pronounced with its full sound as in "h-yoo-manity."
It has three short vowel sounds, for the A, the E, and the I.
It has two short vowel sounds, the A and the I.
Both the A and I in rapid have short vowel sounds.
Yes, the word "cavity" has a short vowel sound. The "a" in "cavity" is pronounced with a short "a" sound like in "cat."
In focus, the o has a long vowel sound and the u has a short vowel sound.
Short vowel sound. Words such as ice and item are long I vowel sounds.
"Afraid" has two vowel sounds. One of them is short and the other is long.
Denim is a short vowel word because the "i" is pronounced with a short sound like in "den."
Both the A and the I in grabbing have short vowel sounds.
The word "rapid" has two short vowel sounds, A and I.
The word "rapid" has a short vowel sound. The "a" in "rapid" is pronounced as /æ/, which is a short vowel sound.