文中共有10处语言错误。错误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

文中共有10处语言错误。错误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.每处错误及修改均仅限一词。
2.只允许修改10处，多者（从11处起）不记分。
One afternoon, I was doing my homework, suddenly I heard someone knocking at
the door. I rose my head, looking out of the window to see who it was. The man of
about 50 with broad shoulders and glasses were standing on the door steps. He was
tall, wearing in an old army coat. He grew a wild beard. A big black hat was pulling
forward over his eyes so that it was hard to see his face clear. His shoes were old and
worn out. It was a big hole in one of his socks. He had with him a black box in one
hand. Only after I took a few more closer look at him I recognize that he used to be
my neighbor ten years age.add “while or when” before I was  / or change “suddenly” to when or and suddenly