增加：在缺词处加一个漏字符号（∧），并在此符号下面写出该加的词。

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。

    Once there had a wooden pagoda（塔）in my village. It had a history of over eight hundreds years. It was such beautiful and famous that many tourists came to visit it every year. They took photos, write down their names on the walls and even threw rubbishes everywhere.

    Later the pagoda was destroyed because of a fire in the forest nearby it. The villagers had to spend a great deal of money build another pagoda, that looked like the old one. Now not only the villagers realize the importance of protecting the pagoda but also tourists know that they should try his best not to cause damage to it.

如图所示，让金属棒ab水平向右运动时，灵敏电流计指针摆动。此实验装置是研究____的，____机就是利用这种现象制成的。将磁极上下对调，其他不变，观察指针摆动情况，这样操作是为了研究____。

图1是撒哈拉以南的非洲政区图，图2是非洲气候图。读图回答问题。