what was she doing when she sliped and hurt herself?我总回答颠倒,这

what was she doing when she sliped and hurt herself?
意思是：她做什么的时候滑到了并伤了自己?
回答she was getting off the bus when she was sliped hurt herself.
之所以比你的回答更好,是因为：
问题问的是她当时在做什么,所以你应该先答她在做什么
也就是she was getting off the bus（这才是问题what对应的回答）
换一个角度来看：
问题what was she doing when she sliped and hurt herself?
你将前半句what was she doing 回答了,也就是she was getting off the bus
然后再把问题里的后半句加上,就变成了:
she was getting off the bus when she was sliped hurt herself.
同理：
what was he doing when he cut himself?
先回答what：he was shaving
然后加上后面的时间：he was shaving when he cut himself
when did he cut himself?
他什么时候把自己伤着了?
he cut himself while he was shaving.
他剃须时伤着了自己.
问题问的是when,而英语里一般把时间状语放在后面,并且英语里会吧重点信息放在前面,这句话的中心是“他弄伤了自己”,所以答案就变成he cut himself while he was shaving.这样了……
中国的教育还是比较照本宣科的,其实学英语的目的在于沟通,太较真实在没有意思.
Anyway,不知我说清楚了没,

what was he doing when he cut himself?这句是问：当他割到自己的时候,他正在干什麼?
when did he cut himself?
he cut himself while he was shaving.翻译: 他什麼时候割到自己的?他在剃须时割到自己.