题目内容：

假定英语课上老师要求同桌之间交换修改作文，请你修改你同桌写的以下作文。文中共有10处语言错误，每句中最多有两处。错误涉及一个单词的增加、删除或修改。

增加：在缺词处加一个漏字符号（∧），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）不计分。

Great changes have been taken place in my village. Ten years ago, the small and low houses of my village lie on the north of a lake. The villagers produced many waste. As a result, the lake was serious polluted. To the west of the village was a sandy field, where was the source of much dust.

Now the poor house have been replaced by green trees. However, the sandy field that the villagers used to plough has been covered of fruit trees. On the lake, now clean and clear, the villagers often spend their spare time fish.

In word, my village has become a green one.