Q: How do you make a trombone sound like a french horn?
A: Stick your hand in the bell and play lots of wrong notes.

Q: How do you make a french horn sound like a trombone?
A: Take your hand out of the bell and lose all sense of taste.

Q: How do you make a french horn sound like a trombone?
A: Take your hand out of the bell and miss all of the notes.

Q: What's the definition of a gentleman?
A: Somone who knows how to play the trombone and doesn't.

Q: What is the difference between a trombone and a trumpet?
A: A trombone will bend before it breaks.

Q: There is a frog driving east and a trombonist walking west. What can be surmised from this?
A: The frog's probably on its way to a gig.

Orchestral trombonists count so much rest and play so many repeated figures that the sheep story also works.

Trombone: a slide whistle with delusions of granduer.