原文journey down the mekong

　　JOURNEY DOWN THE MEKONG
　　PART 1 THE DREAM AND THE PLAN
　　My name is Wang Kun.Ever since middle school,my sister Wang Wei and I have dreamed about taking a great bike trip.Two years ago she bought an expensive mountain bike and then she persuaded me to buy one.Last year,she visited our cousins,Dao Wei and Yu Hang at their college in Kunming.They are Dai and grew up in western Yunnan Province near the Lancang River,the Chinese part of the river that is called the Mekong River in other countries.Wang Wei soon got them interested in cycling too.After graduating from college.we finally got the chance to take a bike trip.I asked my sister,"Where are we going?" It was my sister who first had the idea to cycle along the entire Mekong River from where it begins to where it ends.Now she is planning our schedule for the trip.
　　I am fond of my sister but she has one serious shortcoming.She can be really stubborn.Although she didn't know the best way of getting to places,she insisted that she organize the trip properly.Now,I know that the proper way is always her way.I kept asking her,"When are we leaving and when are we coming back?" I asked her whether she had looked at a map yet.Of course,she hadn't; my sister doesn't care about details.So I told her that the source of the Mekong is in Qinghai Province.She gave me a determined look—the kind that said she would not change her mind.When I told her that our journey would begin at an altitude of more than 5,000 metres,she seemed to be excited about it.When I told her the air would be hard to breathe and it would be very cold,she said it would be an interesting experience.I know my sister well.Once she has made up her mind,nothing can change it.Finally,I had to give in.
　　Several months before our trip,Wang Wei and I went to the library.We found a large atlas with good maps that showed details of world geography.From the atlas we could see that the Mekong River begins in a glacier on a * mountain.At first the river is small and the water is clear and cold.Then it begins to move quickly.It becomes rapids as it passes through deep valleys,travelling across western Yunnan Province.Sometimes the river becomes a waterfall and enters wide valleys.We were both surprised to learn that half of the river is in China.After it leaves China and the high altitude,the Mekong becomes wide,brown and warm.As it enters Southeast Asia,its pace slows.It makes wide bends or meanders through low valleys to the plains where rice grows.At last,the river delta enters the South China Sea.