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。每处错误仅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。

We voluntarily participated in an activity organized by our school in Saturday. We got together at the Goodwill Square and handed out leaflets to passers-by, tell them the significance of environmental protection. The leaflets soon attract the attention of the public. Some of us also delivered a public speech to tell people some knowledges about how to protect the environment. They were also told where to take action in a properly and efficient way. This activity was offered us a chance to contribute to our society but I have learned much from it. I think someone should be concerned about our environment and take active part in improving it.