我是一个五年级的小学生,我家离学校较远,因此我每天都会乘坐公共汽车上学、回家,也每天都经过蓬江大桥。日子久了,我发现了一个很难于启齿的问题,那就是我曾经好几次发现有过往的行人在蓬江大桥底下小便!这是一件多么难为情的事啊!为什么那些人能够做得到呢?莫非是小便憋不住了?但也不能当街随便便啊!于是,一个念头冒了出来:“小便该憋吗?”。我在老师的帮助下,展开了调查! I am a grade 5 primary school student. My family is far from school. Therefore, every day I take a bus to school and go home. I also go through the Pengjiang Bridge every day. As time went by, I found a problem that was hard to tell. That was how hard it was for me to find peculiar pedestrians who used to pee under the Pengjiang Bridge several times. Why these people can do it? Could it be that the urine could not hold it anymore? But it was not easy to go out on the street! So, a thought came out: “The urine should hold it?” With the help of my teacher, I started a survey!