英语课上，老师要求同桌同学相互修改作文。假设以下短文为你同桌所写，请你对其进行修改。文中共有10处错误，每句中最多有两处。错误涉及一个单词的增加、删除或修改。
增加：在缺词处加一个漏词符号（^），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。
3．必须按答题要求做题，否则不给分。
This afternoon I was having a PE lesson while I fell down and hurt my foot. I was in greatly pain at that moment, but I tried to act as if nothing has happened until the class was over. Though I had difficulty walk back to my classroom, I still didn’t tell anyone but even refused the offer of help of my classmates. As result, the hurt in my foot became bad. Now I know I am wrong. We can tell others our need for help and accept his help. Some day we can help others in return for. In this way, we can get along to each other happily and peacefully.while → when
网友回答
(答案→)while → when
解析：
【小题1】while → when while后面不能接短暂性动词，when后面可以接短暂性动词。
【小题2】greatly → great 修饰后面的名词pain使用形容词great。
【小题3】 has → had 本句使用过去完成时，表示在我努力尝试之前就已经发生的事情。
【小题4】 walk → walking 固定句式have some difficulty in doing sth做某事有困难。
【小题5】 but → and 上下文之间存在着并列的关系。
【小题6】 result前加a 固定词组as a result结果；
【小题7】bad → worse 句意分析，这里是指身体受伤的部位更为疼痛。
【小题8】 his → their 这里的their是指上句的others表示的是复数形式。
【小题9】return后去掉for 这里的介词for是多余的，如果加for后面要接宾语。
【小题10】 to → with 固定词组get along with…与…相处。