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。

    "Practice makes perfect" was an old saying.It tells us that it does not any matter if we are slow at doing something.As long as we keep on trying and practice,we'll do a good job at the end.The saying is especial useful in English study.Since a student is poor at speaking,he should catch every chance to open mouth and speak English.His oral English may be excellent one day as a result of his hard works.Not only is the saying useful in English study,but it is helpful in our daily life as well.To some degree,it is no easy way in doing everything since the key to succeed lies in "Practice makes perfect".

2011年12月20日出现月全食，可以看到月全食全过程的国家正确的有

植物和动物生命活动的基本结构功能单位是（　　）