Answer:
I am used when you jump off a bridge for fun.
I am a word with 5 letters. Bold are the first; true are the second; playful are the third; clever are the fourth; forceful are the fifth.
There was a girl half my age when I was 12, now I am 66, how old is she?
I am in the past, never in the future. I don't exist, but have existed. I saw what you saw, and this is what I will ever see. What am I?
What do people spend a lot of money on every year, but never want to use?
Though not a plant, has leaves. Though not a beast, has spine. Though many wouldn't need this thing, It's more valuable than wine.