题目

Have you ever thought of taking a train and having an adventure (奇遇)？Riding the train can be a real adventure.That is how I feel every time I take Amtrak.I often take a four­hour trip to visit my children.Every time I take this trip I never know what  will happen. Last week when I was on the train and over an hour into the train ride，there was a man sitting by himself in the back of the train carrying on a mobile phone conversation— in another language.It was loud and disturbed most of the people on the train.I think it was annoying. Fortunately I sat next to a wonderful ol11．把一条5米长的线对折再对折一次后，每段长是全长的$\frac{1}{4}$，每段长是$1\frac{1}{4}$米．