My friend Jimmy likes to go hunting, just like my uncle. Last year, Jimmy met my uncle (a seasoned hunter), and asked him how to hunt for a bear. So my uncle told him:"Bears like to stay in caves. Usually, I would find a big cave, and throw some rocks into it. If I hear a 'whooo whooo' sound from inside the cave, then I know there's a bear in it. If I fire a couple of shots into the cave, I will get myself a bear." So, one month later, my uncle came across Jimmy at a local bar. Jimmy was all wrapped up in bandages. My uncle was surprised and asked Jimmy what happened. Jimmy said:"Hei I went bear hunting! I followed your advice and found big cave. I threw a rock into it, and guest what, the 'whooo whooo' sound came from inside the cave just like you said. Then I approaced the cave opening, but......before I manage to fire my rifle...... ... ... ... ... ... ... ... ... ... ... ... ... a train came out of the cave......"