She slipped and hurt herself while she was getting off the b

你好。合并下列句子,如果你会,你在这方面的问题就解决了：
He was getting off the bus。 He fell and hurt himself
1 While he was getting off the bus,he fell and hurt himself
2 When he fell and hurt himself,he was getting off the bus
3 He was getting off the bus when he fell and hurt himself
4 He fell and hurt himself while he was getting off the bus。
5 As he got off the bus, he fell and hurt himself
6 He fell and hurt himself as he got off the bus。
简单易懂,没有长篇大论,不过你需要比较和记住。
再问： 不是说 When we were talking, the teacher came in。 When the teacher came in, we were talking。 但是我们只能说 While we were talking, the teacher came in。因为come是瞬间动词 但是She slipped and hurt herself while she was getting off the bus。中get off下车也是瞬间动词啊，为什么就可以用呢