as在这里是一个连词,相当于when引导时间状语从句i did so。so指代前面的I applied这件事情。
不可以在did后面加it,因为和so重复。
that后面的成分是非谓语动词引导的fearing的宾语从句,表示申请时候的心理状态。as I did so 是时间状语从句,可以放在整个句子后面。
(Being short of money and wanting to do something useful原因状语),( I主 applied谓),【 fearing)( as I did so时间状语从句,as连词),( that without a degree and with no experience of teaching条件状语 my chances of landing the job主 were系 slim表:宾语从句)伴随状语】
语序没必要改。