假设你参加所在年级的英文写作比赛，请根据下图和提示完成一篇短文：
1.点明主题；
2.联系实际，谈谈出现此现象的原因及解决办法。
注意：开头已给出，不计入词数；词数不少于120个；
提示词：蜗牛snail 交通拥挤  heavy traffic
 
From the picture we can see two snails are joking about the cars which are moving very slowly on the crowded roads._                                 
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