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。

    I am interesting in spiders (蜘蛛), so this summer I watched them for quite long lime. Spiders don't look beautifully, but they have their own way of killing flying insects. They often build “bridges” between branch. They climb up a branch slowly, pulling some silk. Then they pull the silk towards another branch. When they built many “bridges”, they begin to form webs. As long as insects happen to touch the webs, no matter what hard they try, they can't escape. One day, there was a stronger wind, and the webs were broken, but the spiders still went on to building their “bridges”. They are not afraid with difficulties. As students, we should learn from it.

在等边△ABC中，