Last summer, I went on a river trek (徒步旅行) with my mother and some British friends. The river was not wide, but it was   1   fast. The rocks in the river were so slippery (滑的) that it was   2   for us to walk. We walked   3  , but the freezing water still flooded into our shoes and trousers. I was getting very cold and tired. I wanted to   4  , but when I saw other kids moving so fast, I felt ashamed (惭愧的). This encouraged me to keep following them,   5   I was far behind. It was even more difficult during the last part of the walk. I became so exhausted that I   6   my footing and fell several times. But with the   7   of my mother and my friends, I got to my feet and kept going each time I fell.