同学你好，该知识点来自沪江网校《英语零基础直达大学六级【全额奖学金班】》的课程，想要更系统的学习，欢迎进入课程学习。不仅可以和更多的同学一起学习，而且还有老师、助教随时的学习指导和知识点解答哦。

同学你好~
I could hear people shouting and being anxious.
and being anxious是听不出来的，应该去掉

On arriving at the scene, I stood among the crowd and saw a boy whose arm was stuck in the drain cover.
stood among the crowd and 这部分意思有些冗余，可以去掉

She asked the boy if she could help him and he agreed.
help him可以改成have a try 尝试一下

Then she rubbed his arm with butter, but the boy was not get his arm out.
was改成could

The boy was soon free and though his arm hurt, he was not upset.
The boy was soon free 和前一句意思重复，去掉
Though his arm was hurt, the boy was not upset. 可以这样表达。

祝同学学习进步~