下面短文中共有10处语言错误。错误涉及一个单词的增加、删除或修改。

增加：在缺词处加上一个漏字符号（∧），并在其下面写出该加的词。

删除：把多余的词用斜线（\）划掉。

修改：在错的词下划一横线，并在该词下面写出修改后的词。

注意： 1. 每处错误及其修改均仅限一词。

2．只允许修改10处，多者（从第11处起）不记分。

One afternoon my father and I go fishing on a riverside. We found the water was very dirty that we could not see the bottom. We found some rubbish or dead fish floating on the water so well. That afternoon, my father and I caught only a smaller fish. Why did fish in the river die? That was because of a lot of factories along the river always poured its waste water and rubbish into the river and the water got polluting（污染）. Thus, most of the fish in the river was killed.

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