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限一词；2.只允许修改10处，多者（从第11处起）不计分。

    Last week, I take part in the Cultural Exchange Week. I enjoyed myself in England. I visited the city museum and several place of interest, which made me have better understanding of the English society, culture and history.

    What's more, I was luckily enough to meet my pen friend Tom there. I stayed at his home. And I'll never forget the days when we spent together. When I left England, he offered to me a dictionary for a gift. It's of great help for me to learn English. I will make full use of them and learn English good.

    I hope Tom will come to China when it's convenience for him!

人皮肤生发层正在分裂的细胞中中心体移向两极时，下列几种酶最活跃的是（　　）

①RNA聚合酶    ②解旋酶    ③ATP水解酶    ④ATP合成酶．

地图反映了人们认识世界的程度，地图的变化记录了人们认识世界的过程。随着地理信息技术的发展，出现了新的地图形式——数字地图。据图，回答问题。

与纸质地图相比，概括数字地图功能方面的特点。