Complex sentence: Shaggy dog stories are long-winded anti-jokes where the punch line is deliberately anticlimactic; the humor here lies in fooling the audience into expecting a typical joke with a punch line.
Split into simpler sentences: Shaggy dog stories are long-winded anti-jokes in which the punch line is deliberately anticlimactic. The humor here lies in fooling the audience into expecting a typical joke with a punch line.